Print roll for postcard printer

ABSTRACT

A supply of print media for use in a digital camera having a printer for printing an image captured by the camera onto the print media, the print media being pre-marked with tokens designating that postage has been paid so that each image printed out on the print media has one such token associated with it.

CROSS REFERENCE TO RELATED APPLICATION

[0001] The present application is a divisional of and claims the benefitof U.S. application Ser. No. 09/113,086 filed on Jul. 10, 1998, theentire contents of which are herein incorporated by reference.

FIELD OF THE INVENTION

[0002] The present invention relates substantially to the concept of adisposable camera having instant printing capabilities and inparticular, discloses a method integrating the electronic components ofa camera system.

BACKGROUND OF THE INVENTION

[0003] Recently, the concept of a “single use” disposable camera hasbecome an increasingly popular consumer item. Disposable camera systemspresently on the market normally include an internal film roll and asimplified gearing mechanism for traversing the film roll across animaging system including a shutter and lensing system. The user, afterutilizing a single film roll returns the camera system to a filmdevelopment center for processing. The film roll is taken out of thecamera system and processed and the prints returned to the user. Thecamera system is then able to be re-manufactured through the insertionof a new film roll into the camera system, the replacement of any wornor wearable parts and the re-packaging of the camera system inaccordance with requirements. In this way, the concept of a single use“disposable” camera is provided to the consumer.

[0004] Recently, a camera system has been proposed by the presentapplicant which provides for a handheld camera device having an internalprint head, image sensor and processing means such that images sense bythe image sensing means, are processed by the processing means andadapted to be instantly printed out by the printing means on demand. Theproposed camera system further discloses a system of internal “printrolls” carrying print media such as film on to which images are to beprinted in addition to ink for supplying to the printing means for theprinting process. The print roll is further disclosed to be detachableand replaceable within the camera system.

[0005] Unfortunately, such a system is likely to only be constructed ata substantial cost and it would be desirable to provide for a moreinexpensive form of instant camera system which maintains a substantialnumber of the quality aspects of the aforementioned arrangement.

[0006] It would be further advantageous to provide for the effectiveinterconnection of the sub components of a camera system.

SUMMARY OF THE INVENTION

[0007] According to the invention, there is provided a recyclable,one-time use, print on demand, digital camera comprising:

[0008] an image sensor device for sensing an image;

[0009] a processing means for processing said sensed image;

[0010] a pagewidth print head for printing said sensed image;

[0011] an ink supply means for supplying ink to the print head; and

[0012] a supply of print media on to which said image is printed, thesupply of print media being pre-marked with tokens designating thatpostage has been paid so that each image printed out on the print mediahas one such token associated with it.

[0013] Preferably, the supply of print media is in the form of a roll,the tokens being pre-printed at regularly spaced intervals on onesurface of the print media.

[0014] Each token may have an address zone and a blank zone for writingassociated with it on said one surface to provide a postcard effect.

[0015] Each image may be printed on an opposed surface of the printmedia.

[0016] The token may be in the form of a postage stamp which is in acurrency of a country in which the camera is bought, with a notice tothat effect being carried on an exterior of that camera. Preferably, thecamera has a sleeve placed about a casing of the camera. The notice maythen be carried on the sleeve of the camera.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Notwithstanding any other forms which may fall within the scopeof the present invention, preferred forms of the invention will now bedescribed, by way of example only, with reference to the accompanyingdrawings in which:

[0018]FIG. 1 illustrates a front perspective view of the assembledcamera of the preferred embodiment;

[0019]FIG. 2 illustrates a rear perspective view, partly exploded, ofthe preferred embodiment;

[0020]FIG. 3 is a perspective view of the chassis of the preferredembodiment;

[0021]FIG. 4 is a perspective view of the chassis illustrating mountingof electric motors;

[0022]FIG. 5 is an exploded perspective view of the ink supply mechanismof the preferred embodiment;

[0023]FIG. 6 is a rear perspective view of the assembled form of the inksupply mechanism of the preferred embodiment;

[0024]FIG. 7 is a front perspective view of the assembled form of theink supply mechanism of the preferred embodiment;

[0025]FIG. 8 is an exploded perspective view of the platten unit of thepreferred embodiment;

[0026]FIG. 9 is a perspective view of the assembled form of the plattenunit;

[0027]FIG. 10 is also a perspective view of the assembled form of theplatten unit;

[0028]FIG. 11 is an exploded perspective view of the printhead recappingmechanism of the preferred embodiment;

[0029]FIG. 12 is a close up, exploded perspective view of the recappingmechanism of the preferred embodiment;

[0030]FIG. 13 is an exploded perspective view of the ink supplycartridge of the preferred embodiment;

[0031]FIG. 14 is a close up, perspective view, partly in section, of theinternal portions of the ink supply cartridge in an assembled form;

[0032]FIG. 15 is a schematic block diagram of one form of chip layer ofthe image capture and processing chip of the preferred embodiment;

[0033]FIG. 16 is an exploded perspective view illustrating the assemblyprocess of the preferred embodiment;

[0034]FIG. 17 illustrates a front exploded perspective view of theassembly process of the preferred embodiment;

[0035]FIG. 18 illustrates a perspective view of the assembly process ofthe preferred embodiment;

[0036]FIG. 19 illustrates a perspective view of the assembly process ofthe preferred embodiment;

[0037]FIG. 20 is a perspective view illustrating the insertion of theplatten unit in the preferred embodiment;

[0038]FIG. 21 illustrates the interconnection of the electricalcomponents of the preferred embodiment;

[0039]FIG. 22 illustrates the process of assembling the preferredembodiment; and

[0040]FIG. 23 is a perspective view further illustrating the assemblyprocess of the preferred embodiment.

DESCRIPTION OF PREFERRED AND OTHER EMBODIMENTS

[0041] Turning initially simultaneously to FIG. 1 and FIG. 2 there areillustrated perspective views of an assembled camera constructed inaccordance with the preferred embodiment with FIG. 1 showing a frontperspective view and FIG. 2 showing a rear perspective view. The camera1 includes a paper or plastic film jacket 2 which can include simplifiedinstructions 3 for the operation of the camera system 1. The camerasystem 1 includes a first “take” button 4 which is depressed to capturean image. The captured image is output via output slot 6. A further copyof the image can be obtained through depressing a second “printer copy”button 7 whilst an LED light 5 is illuminated. The camera system alsoprovides the usual viewfinder 8 in addition to a CCD imagecapture/lensing system 9.

[0042] The camera system 1 provides for a standard number of outputprints after which the camera system 1 ceases to function. A prints leftindicator slot 10 is provided to indicate the number of remainingprints. A refund scheme at the point of purchase is assumed to beoperational for the return of used camera systems for recycling.

[0043] Turning now to FIG. 3, the assembly of the camera system is basedaround an internal chassis 12 which can be a plastic injection moldedpart. A pair of paper pinch rollers 28, 29 utilized for de-curling aresnap fitted into corresponding frame holes eg. 26, 27.

[0044] As shown in FIG. 4, the chassis 12 includes a series of mutuallyopposed prongs e.g. 13, 14 into which is snapped fitted a series ofelectric motors 16, 17. The electric motors 16, 17 can be entirelystandard with the motor 16 being of a stepper motor type. The motors16,17 include cogs 19, 20 for driving a series of gear wheels. A firstset of gear wheels is provided for controlling a paper cutter mechanismand a second set is provided for controlling print roll movement.

[0045] Turning next to FIGS. 5 to 7, there is illustrated an ink supplymechanism 40 utilized in the camera system. FIG. 5 illustrates a rearexploded perspective view, FIG. 6 illustrates a rear assembledperspective view and FIG. 7 illustrates a front assembled view. The inksupply mechanism 40 is based around an ink supply cartridge 42 whichcontains printer ink and a print head mechanism for printing outpictures on demand. The ink supply cartridge 42 includes a side aluminumstrip 43 which is provided as a shear strip to assist in cutting imagesfrom a paper roll.

[0046] A dial mechanism 44 is provided for indicating the number of“prints left”. The dial mechanism 44 is snap fitted through acorresponding mating portion 46 so as to be freely rotatable.

[0047] As shown in FIG. 6, the mechanism 40 includes a flexible PCBstrip 47 which. interconnects with the print head and provides forcontrol of the print head. The interconnection between the Flex PCBstrip and an image sensor and print head chip can be via Tape AutomatedBonding (TAB) strips 51, 58. A molded aspherical. lens and aperture shim50 (FIG. 5) is also provided for imaging an image onto the surface ofthe image sensor chip normally located within cavity 53 and a light boxmodule or hood 52 is provided for snap fitting over the cavity 53 so asto provide for proper light control. A series of decoupling capacitorse.g. 34 can also be provided. Further a plug 45 (FIG. 7) is provided forre-plugging ink holes after refilling. A series of guide prongs e.g.55-57 are further provided for guiding the flexible PCB strip 47.

[0048] The ink supply mechanism 40 interacts with a platten unit 60which guides print media under a printhead located in the ink supplymechanism. FIG. 8 shows an exploded view of the platten unit 60, whileFIGS. 9 and 10 show assembled views of the platten unit. The plattenunit 60 includes a first pinch roller 61 which is snap fitted to oneside of a platten base 62. Attached to a second side of the platten base62 is a cutting mechanism 63 which traverses the platen unit 60 by meansof a rod 64 having a screw thread which is rotated by means of coggedwheel 65 which is also fitted to the platten base 62. The screw threadedrod 64 mounts a block 67 which includes a cutting wheel 68 fastened viaa fastener 69. Also mounted to the block 67 is a counter actuator whichincludes a pawl. The pawl 71 acts to rotate the dial mechanism 44 ofFIG. 6 upon the return traversal of the cutting wheel. As shownpreviously in FIG. 6, the dial mechanism 44 includes a cogged surfacewhich interacts with pawl 71 thereby maintaining a count of the numberof photographs by means of numbers embossed on the surface of dialmechanism 44. The cutting mechanism 63 is inserted into the platten base62 by means of a snap fit via clips e.g. 74.

[0049] The platen unit 60 includes an internal recapping mechanism 80for recapping the printhead when not in use. The recapping mechanism 80includes a sponge portion 81 and is operated via a solenoid coil so asto provide for recapping of the print head. In the preferred embodiment,there is provided an inexpensive form of printhead re-capping mechanismprovided for incorporation into a handheld camera system so as toprovide for printhead re-capping of an inkjet printhead.

[0050]FIG. 11 illustrates an exploded view of the recapping mechanismwhilst FIG. 12 illustrates a close up of the end portion thereof. There-capping mechanism 80 is structured around a solenoid including a 16turn coil 75 which can comprise insulated wire. The coil 75 is turnedaround a first stationery solenoid arm 76 which is mounted on a bottomsurface of the platen base 62 (FIG. 8) and includes a post portion 77 tomagnify effectiveness of operation. The arm 76 can comprise a ferrousmaterial.

[0051] A second moveable arm 78 of the solenoid actuator is alsoprovided. The arm 78 is moveable and is also made of ferrous material.Mounted on the arm is a sponge portion surrounded by an elastomer strip79. The elastomer strip 79 is of a generally arcuate cross-section andacts as a leaf spring against the surface of the printhead ink supplycartridge 42 (FIG. 5) so as to provide for a seal against the surface ofthe printhead ink supply cartridge 42. In the quiescent position anelastomer spring unit 87, 88 acts to resiliently deform the elastomerseal 79 against the surface of the ink supply unit 42.

[0052] When it is desired to operate the printhead unit, upon theinsertion of paper, the solenoid coil 75 is activated so as to cause thearm 78 to move down to be adjacent to the end plate 76. The arm 78 isheld against end plate 76 while the printhead is printing by means of asmall “keeper current” in coil 75. Simulation results indicate that thekeeper current can be significantly less than the actuation current.Subsequently, after photo printing, the paper is guillotined by thecutting mechanism 63 of FIG. 8 acting against aluminum strip 43, andrewound so as to clear the area of the re-capping mechanism 80.Subsequently, the current is turned off and springs 87, 88 return thearm 78 so that the elastomer seal is again resting against the printheadink supply cartridge.

[0053] It can be seen that the preferred embodiment provides for asimple and inexpensive means of re-capping a printhead through theutilization of a solenoid type device having a long rectangular form.Further, the preferred embodiment utilizes minimal power in thatcurrents are only required whilst the device is operational andadditionally, only a low keeper current is required whilst the printheadis printing.

[0054] Turning next to FIG. 13 and 14, FIG. 13 illustrates an explodedperspective of the ink supply cartridge 42 whilst FIG. 14 illustrates aclose up sectional view of a bottom of the ink supply cartridge with theprinthead unit in place. The ink supply cartridge 42 is based around apagewidth printhead 102 which comprises a long slither of silicon havinga series of holes etched on the back surface for the supply of ink to afront surface of the silicon wafer for subsequent ejection via a microelectromechanical system. The form of ejection can be many differentforms such as those set out in the tables below.

[0055] Of course, many other inkjet technologies, as referred to theattached tables below, can also be utilized when constructing aprinthead unit 102. The fundamental requirement of the ink supplycartridge 42 is the supply of ink to a series of color channels etchedthrough the back surface of the printhead 102. In the description of thepreferred embodiment, it is assumed that a three color printing processis to be utilized so as to provide full color picture output. Hence, theprint supply unit includes three ink supply reservoirs being a cyanreservoir 104, a magenta reservoir 105 and a yellow reservoir 106. Eachof these reservoirs is required to store ink and includes acorresponding sponge type material 107-109 which assists in stabilizingink within the corresponding ink channel and inhibiting the ink fromsloshing back and forth when the printhead is utilized in a handheldcamera system. The reservoirs 104, 105, 106 are formed through themating of first exterior plastic piece 110 and a second base piece 111.

[0056] At a first end 118 of the base piece 111 a series of air inlet113-115 are provided. Each air inlet leads to a corresponding windingchannel which is hydrophobically treated so as to act as an inkrepellent and therefore repel any ink that may flow along the air inletchannel. The air inlet channel further takes a convoluted path assistingin resisting any ink flow out of the chambers 104-106. An adhesive tapeportion 117 is provided for sealing the channels within end portion 118.

[0057] At the top end, there is included a series of refill holes (notshown) for refilling corresponding ink supply chambers 104, 105, 106. Aplug 121 is provided for sealing the refill holes.

[0058] Turning now to FIG. 14, there is illustrated a close upperspective view, partly in section through the ink supply cartridge 42of FIG. 13 when formed as a unit. The ink supply cartridge includes thethree color ink reservoirs 104, 105, 106 which supply ink to differentportions of the back surface of printhead 102 which includes a series ofapertures 128 defined therein for carriage of the ink to the frontsurface.

[0059] The ink supply cartridge 42 includes two guide walls 124, 125which separate the various ink chambers and are tapered into an endportion abutting the surface of the printhead 102. The guide walls 124,125 are further mechanically supported by block portions e.g. 126 whichare placed at regular intervals along the length of the ink supply unit.The block portions 126 have space at portions close to the back ofprinthead 102 for the flow of ink around the back surface thereof.

[0060] The ink supply unit is preferably formed from a multi-partplastic injection mold and the mold pieces e.g. 110, 111 (FIG. 13) snaptogether around the sponge pieces 107, 109. Subsequently, a syringe typedevice can be inserted in the ink refill holes and the ink reservoirsfilled with ink with the air flowing out of the air outlets 113-115.Subsequently, the adhesive tape portion 117 and plug 121 are attachedand the printhead tested for operation capabilities. Subsequently, theink supply cartridge 42 can be readily removed for refilling by means ofremoving the ink supply cartridge, performing a washing cycle, and thenutilizing the holes for the insertion of a refill syringe filled withink for refilling the ink chamber before returning the ink supplycartridge 42 to a camera.

[0061] Turning now to FIG. 15, there is shown an example layout of theImage Capture and Processing Chip (ICP) 48. The Image Capture andProcessing Chip 48 provides most of the electronic functionality of thecamera with the exception of the print head chip. The chip 48 is ahighly integrated system. It combines CMOS image sensing, analog todigital conversion, digital image processing, DRAM storage, ROM, andmiscellaneous control functions in a single chip.

[0062] The chip is estimated to be around 32 mm² using a leading edge0.18 micron CMOS/DRAM/APS process. The chip size and cost can scalesomewhat with Moore's law, but is dominated by a CMOS active pixelsensor array 201, so scaling is limited as the sensor pixels approachthe diffraction limit.

[0063] The ICP 48 includes CMOS logic, a CMOS image sensor, DRAM, andanalog circuitry. A very small amount of flash memory or othernon-volatile memory is also preferably included for protection againstreverse engineering.

[0064] Alternatively, the ICP can readily be divided into two chips: onefor the CMOS imaging array, and the other for the remaining circuitry.The cost of this two chip solution should not be significantly differentthan the single chip ICP, as the extra cost of packaging and bond-padarea is somewhat cancelled by the reduced total wafer area requiring thecolor filter fabrication steps.

[0065] The ICP preferably contains the following functions: Function 1.5megapixel image sensor Analog Signal Processors Image sensor columndecoders Image sensor row decoders Analogue to Digital Conversion (ADC)Column ADC's Auto exposure 12 Mbits of DRAM DRAM Address Generator Colorinterpolator Convolver Color ALU Halftone matrix ROM Digital halftoningPrint head interface 8 bit CPU core Program ROM Flash memory ScratchpadSRAM Parallel interface (8 bit) Motor drive transistors (5) Clock PLLJTAG test interface Test circuits Busses Bond pads

[0066] The CPU, DRAM, Image sensor, ROM, Flash memory, Parallelinterface, JTAG interface and ADC can be vendor supplied cores. The ICPis intended to run on 1.5V to minimize power consumption and allowconvenient operation from two AA type battery cells.

[0067]FIG. 15 illustrates a layout of the ICP 48. The ICP 48 isdominated by the imaging array 201, which consumes around 80% of thechip area. The imaging array is a CMOS 4 transistor active pixel designwith a resolution of 1,500×1,000. The array can be divided into theconventional configuration, with two green pixels, one red pixel, andone blue pixel in each pixel group. There are 750×500 pixel groups inthe imaging array.

[0068] The latest advances in the field of image sensing and CMOS imagesensing in particular can be found in the October, 1997 issue of IEEETransactions on Electron Devices and, in particular, pages 1689 to 1968.Further, a specific implementation similar to that disclosed in thepresent application is disclosed in Wong et al., “CMOS Active PixelImage Sensors Fabricated Using a 1.8V, 0.25 μm CMOS Technology”, IEDM1996, page 915

[0069] The imaging array uses a 4 transistor active pixel design of astandard configuration. To minimize chip area and therefore cost, theimage sensor pixels should be as small as feasible with the technologyavailable. With a four transistor cell, the typical pixel size scales as20 times the lithographic feature size. This allows a minimum pixel areaof around 3.6 μm×3.6 μm. However, the photosite must be substantiallyabove the diffraction limit of the lens. It is also advantageous to havea square photosite, to maximize the margin over the diffraction limit inboth horizontal and vertical directions. In this case, the photosite canbe specified as 2.5 μm×2.5 μm. The photosite can be a photogate, pinnedphotodiode, charge modulation device, or other sensor.

[0070] The four transistors are packed as an ‘L’ shape, rather than arectangular region, to allow both the pixel and the photosite to besquare. This reduces the transistor packing density slightly, increasingpixel size. However, the advantage in avoiding the diffraction limit isgreater than the small decrease in packing density.

[0071] The transistors also have a gate length which is longer than theminimum for the process technology. These have been increased from adrawn length of 0.18 micron to a drawn length of 0.36 micron. This is toimprove the transistor matching by making the variations in gate lengthrepresent a smaller proportion of the total gate length.

[0072] The extra gate length, and the ‘L’ shaped packing, mean that thetransistors use more area than the minimum for the technology. Normally,around 8 μm² would be required for rectangular packing. Preferably, 9.75μm² has been allowed for the transistors.

[0073] The total area for each pixel is 16 μm², resulting from a pixelsize of 4 μm×4 μm. With a resolution of 1,500×1,000, the area of theimaging array 101 is 6,000 μm×4,000 μm, or 24 mm².

[0074] The presence of a color image sensor on the chip affects theprocess required in two major ways:

[0075] The CMOS fabrication process should be optimised to minimize darkcurrent

[0076] Color filters are required. These can be fabricated using dyedphotosensitive polyimides, resulting in an added process complexity ofthree spin coatings, three photolithographic steps, three developmentsteps, and three hardbakes.

[0077] There are 15,000 analog signal processors (ASPs) 205, one foreach of the columns of the sensor. The ASPs amplify the signal, providea dark current reference, sample and hold the signal, and suppress thefixed pattern noise (FPN).

[0078] There are 375 analog to digital converters 206, one for each fourcolumns of the sensor array. These may be delta-sigma or successiveapproximation type ADC's. A row of low column ADC's are used to reducethe conversion speed required, and the amount of analog signaldegradation incurred before the signal is converted to digital. Thisalso eliminates the hot spot (affecting local dark current) and thesubstrate coupled noise that would occur if a single high speed ADC wasused. Each ADC also has two four bit DAC's which trim the offset andscale of the ADC to further reduce FPN variations between columns. TheseDAC's are controlled by data stored in flash memory during chip testing.

[0079] The column select logic 204 is a 1:1500 decoder which enables theappropriate digital output of the ADCs onto the output bus. As each ADCis shared by four columns, the least significant two bits of the rowselect control 4 input analog multiplexors.

[0080] A row decoder 207 is a 1:1000 decoder which enables theappropriate row of the active pixel sensor array. This selects which ofthe 1000 rows of the imaging array is connected to analog signalprocessors. As the rows are always accessed in sequence, the row selectlogic can be implemented as a shift register.

[0081] An auto exposure system 208 adjusts the reference voltage of theADC 205 in response to the maximum intensity sensed during the previousframe period. Data from the green pixels is passed through a digitalpeak detector. The peak value of the image frame period before capture(the reference frame) is provided to a digital to analogue converter(DAC), which generates the global reference voltage for the column ADCs.The peak detector is reset at the beginning of the reference frame. Theminimum and maximum values of the three RGB color components are alsocollected for color correction.

[0082] The second largest section of the chip is consumed by a DRAM 210used to hold the image. To store the 1,500×1,000 image from the sensorwithout compression, 1.5 Mbytes of DRAM 210 are required. This equals 12Mbits, or slightly less than 5% of a 256 Mbit DRAM. The DRAM technologyassumed is of the 256 Mbit generation implemented using 0.18 μm CMOS.

[0083] Using a standard 8F cell, the area taken by the memory array is3.11 mm². When row decoders, column sensors, redundancy, and otherfactors are taken into account, the DRAM requires around 4 mm ².

[0084] This DRAM 210 can be mostly eliminated if analog storage of theimage signal can be accurately maintained in the CMOS imaging array forthe two seconds required to print the photo. However, digital storage ofthe image is preferable as it is maintained without degradation, isinsensitive to noise, and allows copies of the photo to be printedconsiderably later.

[0085] A DRAM address generator 211 provides the write and readaddresses to the DRAM 210. Under normal operation, the write address isdetermined by the order of the data read from the CMOS image sensor 201.This will typically be a simple raster format. However, the data can beread from the sensor 201 in any order, if matching write addresses tothe DRAM are generated. The read order from the DRAM 210 will normallysimply match the requirements of a color interpolator and the printhead. As the cyan, magenta, and yellow rows of the print head arenecessarily offset by a few pixels to allow space for nozzle actuators,the colors are not read from the DRAM simultaneously. However, there isplenty of time to read all of the data from the DRAM many times duringthe printing process. This capability is used to eliminate the need forFIFOs in the print head interface, thereby saving chip area. All threeRGB image components can be read from the DRAM each time color data isrequired. This allows a color space converter to provide a moresophisticated conversion than a simple linear RGB to CMY conversion.

[0086] Also, to allow two dimensional filtering of the image datawithout requiring line buffers, data is re-read from the DRAM array.

[0087] The address generator may also implement image effects in certainmodels of camera. For example, passport photos are generated by amanipulation of the read addresses to the DRAM. Also, image framingeffects (where the central image is reduced), image warps, andkaleidoscopic effects can all be generated by manipulating the readaddresses of the DRAM.

[0088] While the address generator 211 may be implemented withsubstantial complexity if effects are built into the standard chip, thechip area required for the address generator is small, as it consistsonly of address counters and a moderate amount of random logic.

[0089] A color interpolator 214 converts the interleaved pattern of red,2× green, and blue pixels into RGB pixels. It consists of three 8 bitadders and associated registers. The divisions are by either 2 (forgreen) or 4 (for red and blue) so they can be implemented as fixedshifts in the output connections of the adders.

[0090] A convolver 215 is provided as a sharpening filter which appliesa small convolution kernel (5×5) to the red, green, and blue planes ofthe image. The convolution kernel for the green plane is different fromthat of the red and blue planes, as green has twice as many samples. Thesharpening filter has five functions:

[0091] to improve the color interpolation from the linear interpolationprovided by the color interpolator, to a close approximation of a sincinterpolation;

[0092] to compensate for the image ‘softening’ which occurs duringdigitisation;

[0093] to adjust the image sharpness to match average consumerpreferences, which are typically for the image to be slightly sharperthan reality. As the single use camera is intended as a consumerproduct, and not a professional photographic products, the processingcan match the most popular settings, rather than the most accurate;

[0094] to suppress the sharpening of high frequency (individual pixel)noise. The function is similar to the ‘unsharp mask’ process; and

[0095] to antialias Image Warping.

[0096] These functions are all combined into a single convolutionmatrix. As the pixel rate is low (less than 1 Mpixel per second) thetotal number of multiplies required for the three color channels is 56million multiplies per second. This can be provided by a singlemultiplier. Fifty bytes of coefficient ROM are also required.

[0097] A color ALU 113 combines the functions of color compensation andcolor space conversion into the one matrix multiplication, which isapplied to every pixel of the frame. As with sharpening, the colorcorrection should match the most popular settings, rather than the mostaccurate.

[0098] A color compensation circuit of the color ALU providescompensation for the lighting of the photo. The vast majority ofphotographs are substantially improved by a simple color compensation,which independently normalizes the contrast and brightness of the threecolor components.

[0099] A color look-up table (CLUT) 212 is provided for each colorcomponent. These are three separate 256×8 SRAMs, requiring a total of6,144 bits. The CLUTs are used as part of the color correction process.They are also used for color special effects, such as stochasticallyselected “wild color” effects.

[0100] A color space conversion system of the color ALU converts fromthe RGB color space of the image sensor to the CMY color space of theprinter. The simplest conversion is a 1's complement of the RGB data.However, this simple conversion assumes perfect linearity of both colorspaces, and perfect dye spectra for both the color filters of the imagesensor, and the ink dyes. At the other extreme is a tri-linearinterpolation of a sampled three dimensional arbitrary transform table.This can effectively match any non-linearity or differences in eithercolor space. Such a system is usually necessary to obtain good colorspace conversion when the print engine is a color electrophotographicHowever, since the non-linearity of a halftoned ink jet output is verysmall, a simpler system can be used. A simple matrix multiply canprovide excellent results. This requires nine multiplies and sixadditions per contone pixel. However, since the contone pixel rate islow (less than 1 Mpixel/sec) these operations can share a singlemultiplier and adder. The multiplier and adder are used in a color ALUwhich is shared with the color compensation function.

[0101] Digital halftoning can be performed as a dispersed dot ordereddither using a stochastic optimized dither cell. A halftone matrix ROM216 is provided for storing dither cell coefficients. A dither cell sizeof 32×32 is adequate to ensure that the cell repeat cycle is notvisible. The three colors-cyan, magenta, and yellow—are all ditheredusing the same cell, to ensure maximum co-positioning of the ink dots.This minimizes ‘muddying’ of the mid-tones which results from bleed ofdyes from one dot to adjacent dots while still wet. The total ROM sizerequired is 1 KByte, as the one ROM is shared by the halftoning unitsfor each of the three colors.

[0102] The digital halftoning used is dispersed dot ordered dither withstochastic optimized dither matrix. While dithering does not produce animage quite as ‘sharp’ as error diffusion, it does produce a moreaccurate image with fewer artifacts. The image sharpening produced byerror diffusion is artificial, and less controllable and accurate than‘unsharp mask’ filtering performed in the contone domain. The high printresolution (1,600 dpi×1,600 dpi) results in excellent quality when usinga well formed stochastic dither matrix.

[0103] Digital halftoning is performed by a digital halftoning unit 217using a simple comparison between the contone information from the DRAM210 and the contents of the dither matrix 216. During the halftoneprocess, the resolution of the image is changed from the 250 dpi of thecaptured contone image to the 1,600 dpi of the printed image. Eachcontone pixel is converted to an average of 40.96 halftone dots.

[0104] The ICP incorporates a 16 bit microcontroller CPU core 219 to runthe miscellaneous camera functions, such as reading the buttons,controlling the motor and solenoids, setting up the hardware, andauthenticating the refill station. The processing power required by theCPU is very modest, and a wide variety of processor cores can be used.As the entire CPU program is run from a small ROM 220 programcompatibility between camera versions is not important, as no externalprograms are run. A 2 Mbit (256 Kbyte) program and data ROM 220 isincluded on chip. Most of this ROM space is allocated to data foroutline graphics and fonts for specialty cameras. The programrequirements are minor. The single most complex task is the encryptedauthentication of the refill station. The ROM requires a singletransistor per bit.

[0105] A Flash memory 221 may be used to store a 128 bit authenticationcode. This provides higher security than storage of the authenticationcode in ROM, as reverse engineering can be made essentially impossible.The Flash memory is completely covered by third level metal, making thedata impossible to extract using scanning probe microscopes or electronbeams. The authentication code is stored in the chip when manufactured.At least two other Flash bits are required for the authenticationprocess: a bit which locks out reprogramming of the authentication code,and a bit which indicates that the camera has been refilled by anauthenticated refill station. The flash memory can also be used to storeFPN correction data for the imaging array. Additionally, a phase lockedloop rescaling parameter is stored for scaling the clocking cycle to anappropriate correct time. The clock frequency does not require crystalaccuracy since no date functions are provided. To eliminate the cost ofa crystal, an on chip oscillator with a phase locked loop 224 is used.As the frequency of an on-chip oscillator is highly variable from chipto chip, the frequency ratio of the oscillator to the PLL is digitallytrimmed during initial testing. The value is stored in Flash memory 221.This allows the clock PLL to control the ink-jet heater pulse width withsufficient accuracy.

[0106] A scratchpad SRAM is a small static RAM 222 with a 6T cell. Thescratchpad provided temporary memory for the 16 bit CPU. 1024 bytes isadequate.

[0107] A print head interface 223 formats the data correctly for theprint head. The print head interface also provides all of the timingsignals required by the print head. These timing signals may varydepending upon temperature, the number of dots printed simultaneously,the print medium in the print roll, and the dye density of the ink inthe print roll.

[0108] The following is a table of external connections to the printhead interface: Connection Function Pins DataBits[0-7] Independentserial data to the eight 8 segments of the printhead BitClock Main dataclock for the print head 1 ColorEnable[0-2] Independent enable signalsfor 3 the CMY actuators, allowing different pulse times for each color.BankEnable[0-1] Allows either simultaneous or interleaved 2 actuation oftwo banks of nozzles. This allows two different print speed/powerconsumption tradeoffs NozzleSelect[0-4] Selects one of 32 banks ofnozzles for 5 simultaneous actuation ParallelXferClock Loads theparallel transfer register with the 1 data from the shift registersTotal 20

[0109] The printhead utilized is composed of eight identical segments,each 1.25 cm long. There is no connection between the segments on theprint head chip. Any connections required are made in the external TABbonding film, which is double sided. The division into eight identicalsegments is to simplify lithography using wafer steppers. The segmentwidth of 1.25 cm fits easily into a stepper field. As the printhead chipis long and narrow (10 cm×0.3 mm), the stepper field contains a singlesegment of 32 print head chips. The stepper field is therefore 1.25cm×1.6 cm. An average of four complete print heads are patterned in eachwafer step.

[0110] A single BitClock output line connects to all 8 segments on theprinthead. The 8 DataBits lines lead one to each segment, and areclocked into the 8 segments on the print head simultaneously (on aBitClock pulse). For example, dot 0 is transferred to segments, dot 750is transferred to segment₁, dot 1500 to segment₂ etc simultaneously.

[0111] The ParallelXferClock is connected to each of the 8 segments onthe printhead, so that on a single pulse, all segments transfer theirbits at the same time.

[0112] The NozzleSelect, BankEnable and ColorEnable lines are connectedto each of the 8 segments, allowing the print head interface toindependently control the duration of the cyan, magenta, and yellownozzle energizing pulses. Registers in the Print Head Interface allowthe accurate specification of the pulse duration between 0 and 6 ms,with a typical duration of 2 ms to 3 ms.

[0113] A parallel interface 125 connects the ICP to individual staticelectrical signals. The CPU is able to control each of these connectionsas memory mapped I/O via a low speed bus.

[0114] The following is a table of connections to the parallelinterface: Connection Direction Pins Paper transport stepper motorOutput 4 Capping solenoid Output 1 Copy LED Output 1 Photo button Input1 Copy button Input 1 Total 8

[0115] Seven high current drive transistors e.g. 227 are required. Fourare for the four phases of the main stepper motor two are for theguillotine motor, and the remaining transistor is to drive the cappingsolenoid. These transistors are allocated 20,000 square microns (600,000F) each. As the transistors are driving highly inductive loads, theymust either be turned off slowly, or be provided with a high level ofback EMF protection. If adequate back EMF protection cannot be providedusing the chip process chosen, then external discrete transistors shouldbe used. The transistors are never driven at the same time as the imagesensor is used. This is to avoid voltage fluctuations and hot spotsaffecting the image quality. Further, the transistors are located as faraway from the sensor as possible.

[0116] A standard JTAG (Joint Test Action Group) interface 228 isincluded in the ICP for testing purposes and for interrogation by therefill station. Due to the complexity of the chip, a variety of testingtechniques are required, including BIST (Built In Self Test) andfunctional block isolation. An overhead of 10% in chip area is assumedfor chip testing circuitry for the random logic portions. The overheadfor the large arrays the image sensor and the DRAM is smaller.

[0117] The JTAG interface is also used for authentication of the refillstation. This is included to ensure that the cameras are only refilledwith quality paper and ink at a properly constructed refill station,thus preventing inferior quality refills from occurring. The camera mustauthenticate the refill station, rather than vice versa. The secureprotocol is communicated to the refill station during the automated testprocedure. Contact is made to four gold plated spots on the ICP/printhead TAB by the refill station as the new ink is injected into the printhead.

[0118]FIG. 16 illustrates a rear view of the next step in theconstruction process whilst FIG. 17 illustrates a front view.

[0119] Turning now to FIG. 16, the assembly of the camera systemproceeds via first assembling the ink supply mechanism 40. The flex PCBis interconnected with batteries 84, only one of which is shown, whichare inserted in the middle portion of a print roll 85 which is wrappedaround a plastic former 86. An end cap 89 is provided at the other endof the print roll 85 so as to fasten the print roll and batteries firmlyto the ink supply mechanism.

[0120] The solenoid coil is interconnected (not shown) to interconnects97, 98 (FIG. 8) which include leaf spring ends for interconnection withelectrical contacts on the Flex PCB so as to provide for electricalcontrol of the solenoid.

[0121] Turning now to FIGS. 17-19 the next step in the constructionprocess is the insertion of the relevant gear trains into the side ofthe camera chassis. FIG. 17 illustrates a front view, FIG. 18illustrates a rear view and FIG. 19 also illustrates a rear view. Thefirst gear train comprising gear wheels 22, 23 is utilized for drivingthe guillotine blade with the gear wheel 23 engaging the gear wheel 65of FIG. 8. The second gear train comprising gear wheels 24, 25 and 26engage one end of the print roller 61 of FIG. 8. As best indicated inFIG. 18, the gear wheels mate with corresponding pins on the surface ofthe chassis with the gear wheel 26 being snap fitted into correspondingmating hole 27.

[0122] Next, as illustrated in FIG. 20, the assembled platten unit 60 isthen inserted between the print roll 85 and aluminum cutting blade 43.

[0123] Turning now to FIG. 21, by way of illumination, there isillustrated the electrically interactive components of the camerasystem. As noted previously, the components are based around a Flex PCBboard and include a TAB film 58 which interconnects the printhead 102with the image sensor and processing chip 48. Power is supplied by twoAA type batteries 83, 84 and a paper drive stepper motor 16 is providedin addition to a rotary guillotine motor 17.

[0124] An optical element 31 is provided for snapping into a top portionof the chassis 12. The optical element 31 includes portions defining anoptical view finder 32, 33 which are slotted into mating portions 35, 36in view finder channel 37. Also provided in the optical element 31 is alensing system 38 for magnification of the prints left number inaddition to an optical pipe element 39 for piping light from the LED 5for external display.

[0125] Turning next to FIG. 22, the assembled unit 90 is then insertedinto a front outer case 91 which includes button 4 for activation ofprintouts.

[0126] Turning now to FIG. 23, next, the unit 90 is provided with asnap-on back cover 93 which includes a slot 6 and copy print button 7. Awrapper label containing instructions and advertising (not shown) isthen wrapped around the outer surface of the camera system and pinchclamped to the cover by means of clamp strip 96 which can comprise aflexible plastic or rubber strip.

[0127] Subsequently, the preferred embodiment is ready for use as a onetime use camera system that provides for instant output images ondemand. It will be evident that the preferred embodiment furtherprovides for a refillable camera system. A used camera can be collectedand its outer plastic cases removed and recycled. A new paper roll andbatteries can be added and the ink cartridge refilled. A series ofautomatic test routines can then be carried out to ensure that theprinter is properly operational. Further, in order to ensure onlyauthorized refills are conducted so as to enhance quality, routines inthe on-chip program ROM can be executed such that the cameraauthenticates the refilling station using a secure protocol. Uponauthentication, the camera can reset an internal paper count and anexternal case can be fitted on the camera system with a new outer label.Subsequent packing and shipping can then take place.

[0128] It will be further readily evident to those skilled in the artthat the program ROM can be modified so as to allow for a variety ofdigital processing routines. In addition to the digitally enhancedphotographs optimized for mainstream consumer preferences, various othermodels can readily be provided through mere re-programming of theprogram ROM. For example, a sepia classic old fashion style output canbe provided through a remapping of the color mapping function. A furtheralternative is to provide for black and white outputs again through asuitable color remapping algorithm. Minimum color can also be providedto add a touch of color to black and white prints to produce the effectthat was traditionally used to colorize black and white photos. Further,passport photo output can be provided through suitable addressremappings within the address generators. Further, edge filters can beutilized as is known in the field of image processing to producesketched art styles. Further, classic wedding borders and designs can beplaced around an output image in addition to the provision of relevantclip arts. For example, a wedding style camera might be provided.Further, a panoramic mode can be provided so as to output the well knownpanoramic format of images. Further, a postcard style output can beprovided through the printing of postcards including postage on the backof a print roll surface. Further, cliparts can be provided for specialevents such as Halloween, Christmas etc. Further, kaleidoscopic effectscan be provided through address remappings and wild color effects can beprovided through remapping of the color lookup table. Many other formsof special event cameras can be provided for example, cameras dedicatedto the Olympics, movie tie-ins, advertising and other special events.

[0129] The operational mode of the camera can be programmed so that uponthe depressing of the take photo a first image is sampled by the sensorarray to determine irrelevant parameters. Next a second image is againcaptured which is utilized for the output. The captured image is thenmanipulated in accordance with any special requirements before beinginitially output on the paper roll. The LED light is then activated fora predetermined time during which the DRAM is refreshed so as to retainthe image. If the print copy button is depressed during thispredetermined time interval, a further copy of the photo is output.After the predetermined time interval where no use of the camera hasoccurred, the onboard CPU shuts down all power to the camera systemuntil such time as the take button is again activated. In this way,substantial power savings can be realized.

[0130] Ink Jet Technologies

[0131] The embodiments of the invention use an ink jet printer typedevice. Of course many different devices could be used. Howeverpresently popular ink jet printing technologies are unlikely to besuitable.

[0132] The most significant problem with thermal inkjet is powerconsumption. This is approximately 100 times that required for highspeed, and stems from the energy-inefficient means of drop ejection.This involves the rapid boiling of water to produce a vapor bubble whichexpels the ink. Water has a very high heat capacity, and must besuperheated in thermal inkjet applications. This leads to an efficiencyof around 0.02%, from electricity input to drop momentum (and increasedsurface area) out.

[0133] The most significant problem with piezoelectric inkjet is sizeand cost. Piezoelectric crystals have a very small deflection atreasonable drive voltages, and therefore require a large area for eachnozzle. Also, each piezoelectric actuator must be connected to its drivecircuit on a separate substrate. This is not a significant problem atthe current limit of around 300 nozzles per print head, but is a majorimpediment to the fabrication of pagewidth print heads with 19,200nozzles.

[0134] Ideally, the inkjet technologies used meet the stringentrequirements of in-camera digital color printing and other high quality,high speed, low cost printing applications. To meet the requirements ofdigital photography, new inkjet technologies have been created. Thetarget features include:

[0135] low power (less than 10 Watts)

[0136] high resolution capability (1,600 dpi or more)

[0137] photographic quality output

[0138] low manufacturing cost

[0139] small size (pagewidth times minimum cross section)

[0140] high speed (<2 seconds per page).

[0141] All of these features can be met or exceeded by the inkjetsystems described below with differing levels of difficulty. forty-fivedifferent inkjet technologies have been developed by the Assignee togive a wide range of choices for high volume manufacture. Thesetechnologies form part of separate applications assigned to the presentAssignee as set out in the table below.

[0142] The inkjet designs shown here are suitable for a wide range ofdigital printing systems, from battery powered one-time use digitalcameras, through to desktop and network printers, and through tocommercial printing systems

[0143] For ease of manufacture using standard process equipment, theprinthead is designed to be a monolithic 0.5 micron CMOS chip with MEMSpost processing. For color photographic applications, the print head is100 mm long, with a width which depends upon the inkjet type. Thesmallest print head designed is IJ38, which is 0.35 mm wide, giving achip area of 35 square mm. The print heads each contain 19,200 nozzlesplus data and control circuitry.

[0144] Ink is supplied to the back of the print head by injection moldedplastic ink channels. The molding requires 50 micron features, which canbe created using a lithographically micromachined insert in a standardinjection molding tool. Ink flows through holes etched through the waferto the nozzle chambers fabricated on the front surface of the wafer. Theprint head is connected to the camera circuitry by tape automatedbonding.

[0145] Cross-referenced Applications

[0146] The following table is a guide to cross-referenced patentapplications filed concurrently herewith and discussed hereinafter withthe reference being utilized in subsequent tables when referring to aparticular case: Docket No. Reference Title IJ01US IJ01 Radiant PlungerInk Jet Printer IJ02US IJ02 Electrostatic Ink Jet Printer IJ03US IJ03Planar Thermoelastic Bend Actuator Ink Jet IJ04US IJ04 StackedElectrostatic Ink Jet Printer IJ05US IJ05 Reverse Spring Lever Ink JetPrinter IJ06US IJ06 Paddle Type Ink Jet Printer IJ07US IJ07 PermanentMagnet Electromagnetic Ink Jet Printer IJ08US IJ08 Planar Swing GrillElectromagnetic Ink Jet Printer IJ09US IJ09 Pump Action Refill Ink JetPrinter IJ10US IJ10 Pulsed Magnetic Field Ink Jet Printer IJ11US IJ11Two Plate Reverse Firing Electromagnetic Ink Jet Printer IJ12US IJ12Linear Stepper Actuator Ink Jet Printer IJ13US IJ13 Gear Driven ShutterInk Jet Printer IJ14US IJ14 Tapered Magnetic Pole Electromagnetic InkJet Printer IJ15US IJ15 Linear Spring Electromagnetic Grill Ink JetPrinter IJ16US IJ16 Lorenz Diaphragm Electromagnetic Ink Jet PrinterIJ17US IJ17 PTFE Surface Shooting Shuttered Oscillating Pressure Ink JetPrinter IJ18US IJ18 Buckle Grip Oscillating Pressure Ink Jet PrinterIJ19US IJ19 Shutter Based Ink Jet Printer IJ20US IJ20 Curling CalyxThermoelastic Ink Jet Printer IJ21US IJ21 Thermal Actuated Ink JetPrinter IJ22US IJ22 Iris Motion Ink Jet Printer IJ23US IJ23 DirectFiring Thermal Bend Actuator Ink Jet Printer IJ24US IJ24 Conductive PTFEBen Activator Vented Ink Jet Printer IJ25US IJ25 Magnetostrictive InkJet Printer IJ26US IJ26 Shape Memory Alloy Ink Jet Printer IJ27US IJ27Buckle Plate Ink Jet Printer IJ28US IJ28 Thermal Elastic Rotary ImpellerInk Jet Printer IJ29US IJ29 Thermoelastic Bend Actuator Ink Jet PrinterIJ30US IJ30 Thermoelastic Bend Actuator Using PTFE and Corrugated CopperInk Jet Printer IJ31US IJ31 Bend Actuator Direct Ink Supply Ink JetPrinter IJ32US IJ32 A High Young's Modulus Thermoelastic Ink Jet PrinterIJ33US IJ33 Thermally actuated slotted chamber wall ink jet printerIJ34US IJ34 Ink Jet Printer having a thermal actuator comprising anexternal coiled spring IJ35US IJ35 Trough Container Ink Jet PrinterIJ36US IJ36 Dual Chamber Single Vertical Actuator Ink Jet IJ37US IJ37Dual Nozzle Single Horizontal Fulcrum Actuator Ink Jet IJ38US IJ38 DualNozzle Single Horizontal Actuator Ink Jet IJ39US IJ39 A single bendactuator cupped paddle ink jet printing device IJ40US IJ40 A thermallyactuated ink jet printer having a series of thermal actuator unitsIJ41US IJ41 A thermally actuated ink jet printer including a taperedheater element IJ42US IJ42 Radial Back-Curling Thermoelastic Ink JetIJ43US IJ43 Inverted Radial Back-Curling Thermoelastic Ink Jet IJ44USIJ44 Surface bend actuator vented ink supply ink jet printer IJ45US IJ45Coil Acutuated Magnetic Plate Ink Jet Printer

[0147] Tables of Drop-on-Demand Inkjets

[0148] Eleven important characteristics of the fundamental operation ofindividual inkjet nozzles have been identified. These characteristicsare largely orthogonal, and so can be elucidated as an elevendimensional matrix. Most of the eleven axes of this matrix includeentries developed by the present assignee.

[0149] The following tables form the axes of an eleven dimensional tableof inkjet types.

[0150] Actuator mechanism (18 types)

[0151] Basic operation mode (7 types)

[0152] Auxiliary mechanism (8 types)

[0153] Actuator amplification or modification method (17 types)

[0154] Actuator motion (19 types)

[0155] Nozzle refill method (4 types)

[0156] Method of restricting back-flow through inlet (10 types)

[0157] Nozzle clearing method (9 types)

[0158] Nozzle plate construction (9 types)

[0159] Drop ejection direction (5 types)

[0160] Ink type (7 types)

[0161] The complete eleven dimensional table represented by these axescontains 36.9 billion possible configurations of inkjet nozzle. Whilenot all of the possible combinations result in a viable inkjettechnology, many million configurations are viable. It is clearlyimpractical to elucidate all of the possible configurations. Instead,certain inkjet types have been investigated in detail. These aredesignated IJ01 to IJ45 above.

[0162] Other inkjet configurations can readily be derived from theseforty-five examples by substituting alternative configurations along oneor more of the eleven axes. Most of the IJ01 to IJ45 examples can bemade into inkjet print heads with characteristics superior to anycurrently available inkjet technology.

[0163] Where there are prior art examples known to the inventor, one ormore of these examples are listed in the examples column of the tablesbelow. The IJ01 to IJ45 series are also listed in the examples column.In some cases, a printer may be listed more than once in a table, whereit shares characteristics with more than one entry.

[0164] Suitable applications include: Home printers, Office networkprinters, Short run digital printers, Commercial print systems, Fabricprinters, Pocket printers, Internet WWW printers, Video printers,Medical imaging, Wide format printers, Notebook PC printers, Faxmachines, Industrial printing systems, Photocopiers, Photographicminilabs etc.

[0165] The information associated with the aforementioned elevendimensional matrix are set out in the following tables. ACTUATORMECHANISM (APPLIED ONLY TO SELECTED INK DROPS) Actuator MechanismDescription Advantages Disadvantages Examples Thermal An electrothermalheater heats the Large force generated High power Canon Bubblejet bubbleink to above boiling point, Simple construction Ink carrier limited towater 1979 Endo et al GB transferring significant heat to the No movingparts Low efficiency patent 2,007,162 aqueous ink. A bubble nucleatesFast operation High temperatures required Xerox heater-in-pit andquickly forms, expelling the Small chip area required High mechanicalstress 1990 Hawkins et al ink. for actuator Unusual materials requiredU.S. Pat. No. The efficiency of the process is Large drive transistors4,899,181 low, with typically less than Cavitation causes actuatorfailure Hewlett-Packard 0.05% of the electrical energy Kogation reducesbubble formation TIJ 1982 Vaught et being transformed into kinetic Largeprint heads are difficult to al U.S. Pat. No. energy of the drop.fabricate 4,490,728 Piezoelectric A piezoelectric crystal such as Lowpower consumption Very large area required for actuator Kyser et al U.S.lead lanthanum zirconate (PZT) is Many ink types can be Difficult tointegrate with electronics Pat. No. 3,946,398 electrically activated,and either used High voltage drive transistors Zoltan U.S. Pat. No.expands, shears, or bends to apply Fast operation required 3,683,2121973 pressure to the ink, ejecting drops. High efficiency Full pagewidthprint heads Stemme U.S. Pat. impractical due to actuator size No.3,747,120 Requires electrical poling in high field Epson Stylusstrengths during manufacture Tektronix IJ04 Electrostrictive An electricfield is used to Low power consumption Low maximum strain (approx.0.01%) Seiko Epson, Usui activate electrostriction in relaxor Many inktypes can be Large area required for actuator due et all JP 253401/96materials such as lead lanthanum used to low strain IJ04 zirconatetitanate (PLZT) or lead Low thermal expansion Response speed is marginal(˜10 μs) magnesium niobate (PMN). Electric field strength High voltagedrive transistors required (approx. 3.5 V/μm) required can be generatedFull pagewidth print heads without difficulty impractical due toactuator size Does not require electrical poling Ferroelectric Anelectric field is used to induce Low power consumption Difficult tointegrate with electronics IJ04 a phase transition between the Many inktypes can be Unusual materials such as PLZSnT antiferroelectric (AFE)and used are required ferroelectric (FE) phase. Fast operation (<1 μs)Actuators require a large area Perovskite materials such as tinRelatively high modified lead lanthanum longitudinal strain zirconatetitanate (PLZSnT) High efficiency exhibit large strains of up to 1%Electric field strength of associated with the AFE to FE around 3 V/μmcan be phase transition. readily provided Electrostatic Conductiveplates are separated Low power consumption Difficult to operateelectrostatic IJ02, IJ04 plates by a compressible or fluid Many inktypes can be devices in an aqueous environment dielectric (usually air).Upon used The electrostatic actuator will application of a voltage, theplates Fast operation normally need to be separated from attract eachother and displace the ink ink, causing drop ejection. The Very largearea required to achieve conductive plates may be in a high forces combor honeycomb structure, or High voltage drive transistors may be stackedto increase the surface required area and therefore the force. Fullpagewidth print heads are not competitive due to actuator sizeElectrostatic A strong electric field is applied Low current consumptionHigh voltage required 1989 Saito et al, pull on ink to the ink,whereupon electrostatic Low temperature May be damaged by sparks due toair U.S. Pat. No. attraction accelerates the ink breakdown 4,799,068towards the print medium. Required field strength increases as al, 1989Miura et the drop size decreases U.S. Pat. No. High voltage drivetransistors 4,810,954 required Tone-jet Electrostatic field attractsdust Permanent An electromagnet directly attracts Low power consumptionComplex fabrication IJ07, IJ10 magnet a permanent magnet, displacingMany ink types can be Permanent magnetic material such aselectromagnetic ink and causing drop ejection. used Neodymium Iron Boron(NdFeB) Rare earth magnets with a field Fast operation required.strength around 1 Tesla can be High efficiency High local currentsrequired used. Examples are: Samarium Easy extension from single Coppermetalization should be used Cobalt (SaCo) and magnetic nozzles topagewidth print for long electromigration lifetime and materials in theneodymium iron heads low resistivity boron family (NdFeB, Pigmented inksare usually infeasible NdDyFeBNb, NdDyFeB, etc) Operating temperaturelimited to the Curie temperature (around 540 K) Soft magnetic A solenoidinduced a magnetic Low power consumption Complex fabrication IJ01, IJ05,IJ08, core electromagnetic field in a soft magnetic core or Many inktypes can be Materials not usually present in a IJ10 yoke fabricatedfrom a ferrous used CMOS fab such as NiFe, CoNiFe, or IJ12, IJ14, IJ15,material such as electroplated iron Fast operation CoFe are requiredIJ17 alloys such as CoNiFe [1], CoFe, High efficiency High localcurrents required or NiFe alloys. Typically, the soft Easy extensionfrom single Copper metalization should be used magnetic material is intwo parts, nozzles to pagewidth print for long electromigration lifetimeand which are normally held apart by heads low resistivity a spring.When the solenoid is Electroplating is required actuated, the two partsattract, High saturation flux density is displacing the ink. required(2.0-2.1 T is achievable with CoNiFe [1]) Magnetic The Lorenz forceacting on a Low power consumption Force acts as a twisting motion IJ06,IJ11, IJ13, Lorenz force current carrying wire in a Many ink types canbe Typically, only a quarter of the IJ16 magnetic field is utilized.used solenoid length provides force in a This allows the magnetic fieldto Fast operation useful direction be supplied externally to the printHigh efficiency High local currents required head, for example with rareearth Easy extension from single Copper metalization should be usedpermanent magnets. nozzles to pagewidth print for long electromigrationlifetime and Only the current carrying wire heads low resistivity needbe fabricated on the print- Pigmented inks are usually infeasible head,simplifying materials requirements. Magnetostriction The actuator usesthe giant Many ink types can be Force acts as a twisting motionFischenbeck, U.S. magnetostrictive effect of used Unusual materials suchas Terfenol-D Pat. No. 4,032,929 materials such as Terfenol-D (an Fastoperation are required IJ25 alloy of terbium, dysprosium and Easyextension from single High local currents required iron developed at theNaval nozzles to pagewidth print Copper metalization should be usedOrdnance Laboratory, hence Ter- heads for long electromigration lifetimeand Fe-NOL). For best efficiency, the High force is available lowresistivity actuator should be pre-stressed to Pre-stressing may berequired approx. 8 MPa. Surface Ink under positive pressure is held Lowpower consumption Requires supplementary force to Silverbrook, EPtension in a nozzle by surface tension. Simple construction effect dropseparation 0771 658 A2 and reduction The surface tension of the ink isNo unusual materials Requires special ink surfactants related patentreduced below the bubble required in fabrication Speed may be limited bysurfactant applications threshold, causing the ink to High efficiencyproperties egress from the nozzle. Easy extension from single nozzles topagewidth print heads Viscosity The ink viscosity is locally Simpleconstruction Requires supplementary force to Silverbrook, EP reductionreduced to select which drops are No unusual materials effect dropseparation 0771 658 A2 and to be ejected. A viscosity required infabrication Requires special ink viscosity related patent reduction canbe achieved Easy extension from single properties applicationselectrothermally with most inks, nozzles to pagewidth print High speedis difficult to achieve but special inks can be engineered headsRequires oscillating ink pressure for a 100:1 viscosity reduction. Ahigh temperature difference (typically 80 degrees) is required AcousticAn acoustic wave is generated and Can operate without a Complex drivecircuitry 1993 Hadimioglu et focussed upon the drop ejection nozzleplate Complex fabrication al, EUP 550,192 region. Low efficiency 1993Elrod et al, Poor control of drop position EUP 572,220 Poor control ofdrop volume Thermoelastic An actuator which relies upon Low powerconsumption Efficient aqueous operation requires a IJ03, IJ09, IJ17,bend actuator differential thermal expansion Many ink types can bethermal insulator on the hot side IJ18 upon Joule heating is used. usedCorrosion prevention can be difficult IJ19, IJ20, IJ21, Simple planarfabrication Pigmented inks may be infeasible, as IJ22 Small chip arearequired pigment particles may jam the bend IJ23, IJ24, IJ27, for eachactuator actuator IJ28 Fast operation IJ29, IJ30, IJ31, High efficiencyIJ32 CMOS compatible IJ33, IJ34, IJ35, voltages and currents IJ36Standard MEMS processes IJ37, IJ38, IJ39, can be used IJ40 Easyextension from single IJ41 nozzles to pagewidth print heads High CTE Amaterial with a very high High force can be Requires special material(e.g. PTFE) IJ09, IJ17, IJ18, thermoelastic coefficient of thermalexpansion generated Requires a PTFE deposition process, IJ20 actuator(CTE) such as PTFE is a candidate for which is not yet standard in ULSIfabs IJ21, IJ22, IJ23, polytetrafluoroethylene (PTFE) is low dielectricconstant PTFE deposition cannot be followed IJ24 used. As high CTEmaterials are insulation in ULSI with high temperature (above 350° C.)IJ27, IJ28, IJ29, usually non-conductive, a heater Very low powerprocessing IJ30 fabricated from a conductive consumption Pigmented inksmay be infeasible, as IJ31, IJ42, IJ43, material is incorporated. A 50μm Many ink types can be pigment particles may jam the bend IJ44 longPTFE bend actuator with used actuator polysilicon heater and 15 mWSimple planar fabrication power input can provide 180 μN Small chip arearequired force and 10 μm deflection. for each actuator Actuator motionsinclude: Fast operation Bend High efficiency Push CMOS compatible Bucklevoltages and currents Rotate Easy extension from single nozzles topagewidth print heads Conductive A polymer with a high coefficient Highforce can be Requires special materials IJ24 polymer of thermalexpansion (such as generated development (High CTE conductivethermoelastic PTFE) is doped with conducting Very low power polymer)actuator substances to increase its consumption Requires a PTFEdeposition process, conductivity to about 3 orders of Many ink types canbe which is not yet standard in ULSI fabs magnitude below that ofcopper. used PTFE deposition cannot be followed The conducting polymerexpands Simple planar fabrication with high temperature (above 350° C.)when resistively heated. Small chip area required processing Examples ofconducting dopants for each actuator Evaporation and CVD depositioninclude: Fast operation techniques cannot be used Carbon nanotubes Highefficiency Pigmented inks may be infeasible, as Metal fibers CMOScompatible pigment particles may jam the bend Conductive polymers suchas voltages and currents actuator doped polythiophene Easy extensionfrom single Carbon granules nozzles to pagewidth print heads Shapememory A shape memory alloy such as High force is available Fatiguelimits maximum number of IJ26 alloy TiNi (also known as Nitinol -(stresses of hundreds of cycles Nickel Titanium alloy developed MPa) Lowstrain (1%) is required to extend at the Naval Ordnance Large strain isavailable fatigue resistance Laboratory) is thermally switched (morethan 3%) Cycle rate limited by heat removal between its weak martensiticstate High corrosion resistance Requires unusual materials (TiNi) andits high stiffness austenic Simple construction The latent heat oftransformation must state. The shape of the actuator in Easy extensionfrom single be provided its martensitic state is deformed nozzles topagewidth print High current operation relative to the austenic shape.The heads Requires pre-stressing to distort the shape change causesejection of a Low voltage operation martensitic state drop. LinearLinear magnetic actuators include Linear Magnetic actuators Requiresunusual semiconductor IJ12 Magnetic the Linear Induction Actuator can beconstructed with materials such as soft magnetic alloys Actuator (LIA),Linear Permanent Magnet high thrust, long travel, (e.g. CoNiFe [1])Synchronous Actuator (LPMSA), and high efficiency using Some varietiesalso require permanent Linear Reluctance Synchronous planarsemiconductor magnetic materials such as Actuator (LRSA), Linearfabrication techniques Neodymium iron boron (NdFeB) Switched ReluctanceActuator Long actuator travel is Requires complex multi-phase drive(LSRA), and the Linear Stepper available circuitry Actuator (LSA).Medium force is available High current operation Low voltage operation

[0166] BASIC OPERATION MODE Operational mode Description AdvantagesDisadvantages Examples Actuator This is the simplest mode of Simpleoperation Drop repetition rate is usually limited Thermal inkjetdirectly operation: the actuator directly No external fields required toless than 10 KHz. However, this is Piezoelectric inkjet IJ01, pushes inksupplies sufficient kinetic energy Satellite drops can be notfundamental to the method, but is IJ02, IJ03, to expel the drop. Thedrop must avoided if drop velocity is related to the refill methodnormally IJ04 have a sufficient velocity to less than 4 m/s used IJ05,IJ06, IJ07, overcome the surface tension. Can be efficient, All of thedrop kinetic energy must be IJ09 depending upon the provided by theactuator IJ11, IJ12, IJ14, actuator used Satellite drops usually form ifdrop IJ16 velocity is greater than 4.5 m/s IJ20, IJ22, IJ23, IJ24 IJ25,IJ26, IJ27, IJ28 IJ29, IJ30, IJ31, IJ32 IJ33, IJ34, IJ35, IJ36 IJ37,IJ38, IJ39, IJ40 IJ41, IJ42, IJ43, IJ44 Proximity The drops to beprinted are Very simple print head Requires close proximity between theSilverbrook, EP selected by some manner (e.g. fabrication can be usedprint head and the print media or 0771 658 A2 and thermally inducedsurface tension The drop selection means transfer roller related patentreduction of pressurized ink). does not need to provide May require twoprint heads printing applications Selected drops are separated from theenergy required to alternate rows of the image the ink in the nozzle bycontact separate the drop from the Monolithic color print heads are withthe print medium or a nozzle difficult transfer roller. ElectrostaticThe drops to be printed are Very simple print head Requires very highelectrostatic field Silverbrook, EP pull on ink selected by some manner(e.g. fabrication can be used Electrostatic field for small nozzle 0771658 A2 and thermally induced surface tension The drop selection meanssizes is above air breakdown related patent reduction of pressurizedink). does not need to provide Electrostatic field may attract dustapplications Selected drops are separated from the energy required toTone-Jet the ink in the nozzle by a strong separate the drop from theelectric field. nozzle Magnetic pull The drops to be printed are Verysimple print head Requires magnetic ink Silverbrook, EP on ink selectedby some manner (e.g. fabrication can be used Ink colors other than blackare 0771 658 A2 and thermally induced surface tension The drop selectionmeans difficult related patent reduction of pressurized ink). does notneed to provide Requires very high magnetic fields applications Selecteddrops are separated from the energy required to the ink in the nozzle bya strong separate the drop from the magnetic field acting on the nozzlemagnetic ink. Shutter The actuator moves a shutter to High speed (>50KHz) Moving parts are required IJ13, IJ17, IJ21 block ink flow to thenozzle. The operation can be achieved Requires ink pressure modulatorink pressure is pulsed at a due to reduced refill time Friction and wearmust be considered multiple of the drop ejection Drop timing can be veryStiction is possible frequency. accurate The actuator energy can be verylow Shuttered grill The actuator moves a shutter to Actuators with smalltravel Moving parts are required IJ08, IJ15, IJ18, block ink flowthrough a grill to can be used Requires ink pressure modulator IJ19 thenozzle. The shutter movement Actuators with small force Friction andwear must be considered need only be equal to the width of can be usedStiction is possible the grill holes. High speed (>50 KHz) operation canbe achieved Pulsed A pulsed magnetic field attracts Extremely low energyRequires an external pulsed magnetic IJ10 magnetic pull an ‘ink pusher’at the drop operation is possible field on ink pusher ejectionfrequency. An actuator No heat dissipation Requires special materialsfor both the controls a catch, which prevents problems actuator and theink pusher the ink pusher from moving when Complex construction a dropis not to be ejected.

[0167] AUXILIARY MECHANISM (APPLIED TO ALL NOZZLES) Auxiliary MechanismDescription Advantages Disadvantages Examples None The actuator directlyfires the ink Simplicity of construction Drop ejection energy must beMost inkjets, drop, and there is no external field Simplicity ofoperation supplied by individual nozzle actuator including or othermechanism required. Small physical size piezoelectric and thermalbubble. IJ01-IJ07, IJ09, IJ11 IJ12, IJ14, IJ20, IJ22 IJ23-IJ45Oscillating ink The ink pressure oscillates, Oscillating ink pressureRequires external ink pressure Silverbrook, EP pressure providing muchof the drop can provide a refill pulse, oscillator 0771 658 A2 and(including acoustic ejection energy. The actuator allowing higheroperating Ink pressure phase and amplitude related patent stimulation)selects which drops are to be fired speed must be carefully controlledapplications by selectively blocking or The actuators may operateAcoustic reflections in the ink IJ08, IJ13, IJ15, enabling nozzles. Theink pressure with much lower energy chamber must be designed for IJ17oscillation may be achieved by Acoustic lenses can be IJ18, IJ19, IJ21vibrating the print head, or used to focus the sound on preferably by anactuator in the the nozzles ink supply. Media The print head is placedin close Low power Precision assembly required Silverbrook, EP proximityproximity to the print medium. High accuracy Paper fibers may causeproblems 0771 658 A2 and Selected drops protrude from the Simple printhead Cannot print on rough substrates related patent print head furtherthan unselected construction applications drops, and contact the printmedium. The drop soaks into the medium fast enough to cause dropseparation. Transfer roller Drops are printed to a transfer Highaccuracy Bulky Silverbrook, EP roller instead of straight to the Widerange of print Expensive 0771 658 A2 and print medium. A transfer rollersubstrates can be used Complex construction related patent can also beused for proximity Ink can be dried on the applications drop separation.transfer roller Tektronix hot melt piezoelectric inkjet Any of the IJseries Electrostatic An electric field is used to Low power Fieldstrength required for separation Silverbrook, EP accelerate selecteddrops towards Simple print head of small drops is near or above air 0771658 A2 and the print medium. construction breakdown related patentapplications Tone-Jet Direct A magnetic field is used to Low powerRequires magnetic ink Silverbrook, EP magnetic field accelerate selecteddrops of Simple print head Requires strong magnetic field 0771 658 A2and magnetic ink towards the print construction related patent medium.applications Cross The print head is placed in a Does not requiremagnetic Requires external magnet IJ06, IJ16 magnetic field constantmagnetic field. The materials to be integrated Current densities may behigh, Lorenz force in a current carrying in the print head resulting inelectromigration problems wire is used to move the actuator.manufacturing process Pulsed A pulsed magnetic field is used to Very lowpower operation Complex print head construction IJ10 magnetic fieldcyclically attract a paddle, which is possible Magnetic materialsrequired in print pushes on the ink. A small Small print head size headactuator moves a catch, which selectively prevents the paddle frommoving.

[0168] ACTUATOR AMPLIFICATION OR MODIFICATION METHOD Actuatoramplification Description Advantages Disadvantages Examples None Noactuator mechanical Operational simplicity Many actuator mechanisms haveThermal Bubble amplification is used. The actuator insufficient travel,or insufficient Inkjet directly drives the drop ejection force, toefficiently drive the drop IJ01, IJ02, IJ06, process. ejection processIJ07 IJ16, IJ25, IJ26 Differential An actuator material expands Providesgreater travel in a High stresses are involved Piezoelectric expansionmore on one side than on the reduced print head area Care must be takenthat the materials IJ03, IJ09, IJ17-IJ24 bend actuator other. Theexpansion may be The bend actuator converts do not delaminate IJ27,IJ29-IJ39, thermal, piezoelectric, a high force low travel Residual bendresulting from high IJ42, magnetostrictive, or other actuator mechanismto temperature or high stress during IJ43, IJ44 mechanism. high travel,lower force formation mechanism. Transient bend A trilayer bend actuatorwhere the Very good temperature High stresses are involved IJ40, IJ41actuator two outside layers are identical. stability Care must be takenthat the materials This cancels bend due to ambient High speed, as a newdrop do not delaminate temperature and residual stress. can be firedbefore heat The actuator only responds to dissipates transient heatingof one side or the Cancels residual stress of other. formation Actuatorstack A series of thin actuators are Increased travel Increasedfabrication complexity Some piezoelectric stacked. This can beappropriate Reduced drive voltage Increased possibility of shortcircuits ink jets where actuators require high due to pinholes IJ04electric field strength, such as electrostatic and piezoelectricactuators. Multiple Multiple smaller actuators are Increases the forceActuator forces may not add linearly, IJ12, IJ13, IJ18, actuators usedsimultaneously to move the available from an actuator reducingefficiency IJ20 ink. Each actuator need provide Multiple actuators canbe IJ22, IJ28, IJ42, only a portion of the force positioned to controlink IJ43 required. flow accurately Linear Spring A linear spring is usedto Matches low travel Requires print head area for the spring IJ15transform a motion with small actuator with higher travel travel andhigh force into a longer requirements travel, lower force motion.Non-contact method of motion transformation Reverse spring The actuatorloads a spring. When Better coupling to the ink Fabrication complexityIJ05, IJ11 the actuator is turned off, the High stress in the springspring releases. This can reverse the force/distance curve of theactuator to make it compatible with the force/time requirements of thedrop ejection. Coiled A bend actuator is coiled to Increases travelGenerally restricted to planar IJ17, IJ21, IJ34, actuator providegreater travel in a reduced Reduces chip area implementations due toextreme IJ35 chip area. Planar implementations fabrication difficulty inother are relatively easy to orientations. fabricate. Flexure bend Abend actuator has a small Simple means of Care must be taken not toexceed the IJ10, IJ19, IJ33 actuator region near the fixture point,increasing travel of a bend elastic limit in the flexure area whichflexes much more readily actuator Stress distribution is very uneventhan the remainder of the actuator. Difficult to accurately model withThe actuator flexing is effectively finite element analysis convertedfrom an even coiling to an angular bend, resulting in greater travel ofthe actuator tip. Gears Gears can be used to increase Low force, lowtravel Moving parts are required IJ13 travel at the expense of duration.actuators can be used Several actuator cycles are required Circulargears, rack and pinion, Can be fabricated using More complex driveelectronics ratchets, and other gearing standard surface MEMS Complexconstruction methods can be used. processes Friction, friction, and wearare possible Catch The actuator controls a small Very low actuatorenergy Complex construction IJ10 catch. The catch either enables or Verysmall actuator size Requires external force disables movement of an inkUnsuitable for pigmented inks pusher that is controlled in a bulkmanner. Buckle plate A buckle plate can be used to Very fast movementMust stay within elastic limits of the S. Hirata et al, “An change aslow actuator into a fast achievable materials for long device lifeInk-jet Head...”, motion. It can also convert a high High stressesinvolved Proc. IEEE MEMS, force, low travel actuator into a Generallyhigh power requirement Feb. 1996, pp 418-423. high travel, medium forcemotion. IJ18, IJ27 Tapered A tapered magnetic pole can Linearizes themagnetic Complex construction IJ14 magnetic pole increase travel at theexpense of force/distance curve force. Lever A lever and fulcrum is usedto Matches low travel High stress around the fulcrum IJ32, IJ36, IJ37transform a motion with small actuator with higher travel travel andhigh force into a requirements motion with longer travel and Fulcrumarea has no linear lower force. The lever can also movement, and can bereverse the direction of travel. used for a fluid seal Rotary Theactuator is connected to a High mechanical Complex construction IJ28impeller rotary impeller. A small angular advantage Unsuitable forpigmented inks deflection of the actuator results The ratio of force totravel in a rotation of the impeller vanes, of the actuator can be whichpush the ink against matched to the nozzle stationary vanes and out ofthe requirements by varying nozzle. the number of impeller vanesAcoustic lens A refractive or diffractive (e.g. No moving parts Largearea required 1993 Hadimioglu et zone plate) acoustic lens is used toOnly relevant for acoustic ink jets al, EUP 550,192 concentrate soundwaves. 1993 Elrod et al, EUP 572,220 Sharp A sharp point is used toSimple construction Difficult to fabricate using standard Tone-jetconductive point concentrate an electrostatic field. VLSI processes fora surface ejecting ink-jet Only relevant for electrostatic ink jets

[0169] ACTUATOR MOTION Actuator motion Description AdvantagesDisadvantages Examples Volume The volume of the actuator Simpleconstruction in the High energy is typically required to Hewlett-Packardexpansion changes, pushing the ink in all case of thermal ink jetachieve volume expansion. This leads Thermal Inkjet directions. tothermal stress, cavitation, and Canon Bubblejet kogation in thermal inkjet implementations Linear, normal The actuator moves in a directionEfficient coupling to ink High fabrication complexity may be IJ01, IJ02,IJ04, to chip surface normal to the print head surface. drops ejectednormal to the required to achieve perpendicular IJ07 The nozzle istypically in the line surface motion IJ11, IJ14 of movement. Linear,parallel The actuator moves parallel to the Suitable for planarFabrication complexity IJ12, IJ13, IJ15, to chip surface print headsurface. Drop ejection fabrication Friction IJ33, may still be normal tothe surface. Stiction IJ34, IJ35, IJ36 Membrane An actuator with a highforce but The effective area of the Fabrication complexity 1982 HowkinsU.S. push small area is used to push a stiff actuator becomes theActuator size Pat. No. 4,459,601 membrane that is in contact withmembrane area Difficulty of integration in a VLSI the ink. processRotary The actuator causes the rotation of Rotary levers may be usedDevice complexity IJ05, IJ08, IJ13, some element, such a grill or toincrease travel May have friction at a pivot point IJ28 impeller Smallchip area requirements Bend The actuator bends when A very small changein Requires the actuator to be made from 1970 Kyser et al energized.This may be due to dimensions can be at least two distinct layers, or tohave U.S. Pat. No. 3,946,398 differential thermal expansion, convertedto a large a thermal difference across the 1973 Stemme U.S. Pat. No.piezoelectric expansion, motion. actuator 3,747,120 magnetostriction, orother form of IJ03, IJ09, IJ10, relative dimensional change. IJ19 IJ23,IJ24, IJ25, IJ29 IJ30, IJ31, IJ33, IJ34 IJ35 Swivel The actuator swivelsaround a Allows operation where Inefficient coupling to the ink motionIJ06 central pivot. This motion is the net linear force on the suitablewhere there are opposite paddle is zero forces applied to opposite sidesof Small chip area the paddle, e.g. Lorenz force. requirementsStraighten The actuator is normally bent, and Can be used with shapeRequires careful balance of stresses to IJ26, IJ32 straightens whenenergized. memory alloys where the ensure that the quiescent bend isaustenic phase is planar accurate Double bend The actuator bends in oneOne actuator can be Difficult to make the drops IJ36, IJ37, IJ38direction when one element is used to power two ejected by both benddirections energized, and bends the other nozzles. identical. way whenanother element is Reduced chip size. A small efficiency loss comparedenergized. Not sensitive to to equivalent single bend ambienttemperature actuators. Shear Energizing the actuator causes a Canincrease the Not readily applicable to other 1985 Fishbeck shear motionin the actuator effective travel of actuator mechanisms U.S. Pat. No.4,584,590 material. piezoelectric actuators Radial The actuator squeezesan ink Relatively easy to High force required 1970 Zoltan constrictionreservoir, forcing ink from a fabricate single Inefficient U.S. Pat. No.3,683,212 constricted nozzle, nozzles from glass Difficult to integratewith VLSI tubing as macroscopic processes structures Coil/uncoil Acoiled actuator uncoils or coils Easy to fabricate as a Difficult tofabricate for non- IJ17, IJ21, IJ34, more tightly. The motion of theplanar VLSI process planar devices IJ35 free end of the actuator ejectsthe Small area required, Poor out-of-plane stiffness ink. therefore lowcost Bow The actuator bows (or buckles) in Can increase the speedMaximum travel is constrained IJ16, IJ18, IJ27 the middle whenenergized. of travel High force required Mechanically rigid Push-PullTwo actuators control a shutter. The structure is pinned Not readilysuitable for inkjets IJ18 One actuator pulls the shutter, and at bothends, so has a which directly push the ink the other pushes it. highout-of-plane rigidity Curl inwards A set of actuators curl inwards toGood fluid flow to the Design complexity IJ20, IJ42 reduce the volume ofink that they region behind the enclose. actuator increases efficiencyCurl outwards A set of actuators curl outwards, Relatively simpleRelatively large chip area IJ43 pressurizing ink in a chamberconstruction surrounding the actuators, and expelling ink from a nozzlein the chamber. Iris Multiple vanes enclose a volume High efficiencyHigh fabrication complexity IJ22 of ink. These simultaneously Small chiparea Not suitable for pigmented inks rotate, reducing the volume betweenthe vanes. Acoustic The actuator vibrates at a high The actuator can beLarge area required for efficient 1993 vibration frequency. physicallydistant from operation at useful frequencies Hadimioglu et the inkAcoustic coupling and crosstalk al, EUP 550,192 Complex drive circuitry1993 Elrod et al, Poor control of drop volume and EUP 572,220 positionNone In various ink jet designs the No moving parts Various othertradeoffs are required to Silverbrook, EP actuator does not move.eliminate moving parts 0771 658 A2 and related patent applicationsTone-jet

[0170] NOZZLE REFILL METHOD Nozzle refill method Description AdvantagesDisadvantages Examples Surface After the actuator is energized, itFabrication simplicity Low speed Thermal inkjet tension typicallyreturns rapidly to its Operational simplicity Surface tension forcerelatively small Piezoelectric inkjet normal position. This rapid returncompared to actuator force IJ01-IJ07, IJ10-IJ14 sucks in air through thenozzle Long refill time usually dominates the IJ16, IJ20, IJ22-IJ45opening. The ink surface tension total repetition rate at the nozzlethen exerts a small force restoring the meniscus to a minimum area.Shuttered Ink to the nozzle chamber is High speed Requires common inkpressure IJ08, IJ13, IJ15, oscillating ink provided, at a pressure thatLow actuator energy, as oscillator IJ17 pressure oscillates at twice thedrop the actuator need only May not be suitable for pigmented IJ18,IJ19, IJ21 ejection frequency. When a drop open or close the shutter,inks is to be ejected, the shutter is instead of ejecting the ink openedfor 3 half cycles: drop drop ejection, actuator return, and refill.Refill actuator After the main actuator has High speed, as the nozzleRequires two independent actuators IJ09 ejected a drop a second (refill)is actively refilled per nozzle actuator is energized. The refillactuator pushes ink into the nozzle chamber. The refill actuator returnsslowly, to prevent its return from emptying the chamber again. Positiveink The ink is held a slight positive High refill rate, therefore aSurface spill must be prevented Silverbrook, EP pressure pressure. Afterthe ink drop is high drop repetition rate is Highly hydrophobic printhead 0771 658 A2 and ejected, the nozzle chamber fills possible surfacesare required related patent quickly as surface tension and inkapplications pressure both operate to refill the Alternative for:nozzle. IJ01-IJ07, IJ10-IJ14 IJ16, IJ20, IJ22-IJ45

[0171] METHOD OF RESTRICTING BACK-FLOW THROUGH INLET Inlet back-flowrestriction method Description Advantages Disadvantages Examples Longinlet The ink inlet channel to the nozzle Design simplicity Restrictsrefill rate Thermal inkjet channel chamber is made long and Operationalsimplicity May result in a relatively large chip Piezoelectric inkjetrelatively narrow, relying on Reduces crosstalk area IJ42, IJ43 viscousdrag to reduce inlet back- Only partially effective flow. Positive inkpressure The ink is under a positive Drop selection and Requires amethod (such as a Silverbrook, EP pressure, so that in the quiescentseparation forces can nozzle rim or effective 0771 658 A2 state some ofthe ink drop already be reduced hydrophobizing, or both) to and relatedprotrudes from the nozzle. Fast refill time prevent flooding of theejection patent This reduces the pressure in the surface of the printhead. applications nozzle chamber which is required Possible to eject acertain volume of ink. operation of the The reduction in chamberfollowing: pressure results in a reduction in IJ01-IJ07, IJ09-IJ12 inkpushed out through the inlet. IJ14, IJ16, IJ20, IJ22, IJ23-IJ34,IJ36-IJ41 IJ44 Baffle One or more baffles are placed in The refill rateis not as Design complexity HP Thermal Ink the inlet ink flow. When therestricted as the long May increase fabrication Jet actuator isenergized, the rapid ink inlet method. complexity (e.g. Tektronix hotTektronix movement creates eddies which Reduces crosstalk meltPiezoelectric print heads). piezoelectric ink restrict the flow throughthe inlet. jet The slower refill process is unrestricted, and does notresult in eddies. Flexible flap In this method recently disclosedSignificantly reduces Not applicable to most inkjet Canon restrictsinlet by Canon, the expanding actuator back-flow for edge-configurations (bubble) pushes on a flexible flap shooter thermal inkjet Increased fabrication complexity that restricts the inlet. devicesInelastic deformation of polymer flap results in creep over extended useInlet filter A filter is located between the ink Additional advantageRestricts refill rate IJ04, IJ12, IJ24, inlet and the nozzle chamber.The of ink filtration May result in complex IJ27 filter has a multitudeof small Ink filter may be construction IJ29, IJ30 holes or slots,restricting ink flow. fabricated with no The filter also removesparticles additional process which may block the nozzle. steps Smallinlet The ink inlet channel to the nozzle Design simplicity Restrictsrefill rate IJ02, IJ37, IJ44 compared to chamber has a substantially Mayresult in a relatively large nozzle smaller cross section than that ofchip area the nozzle, resulting in easier ink Only partially effectiveegress out of the nozzle than out of the inlet. Inlet shutter Asecondary actuator controls the Increases speed of the ink- Requiresseparate refill actuator and IJ09 position of a shutter, closing off jetprint head operation drive circuit the ink inlet when the main actuatoris energized. The inlet is The method avoids the problem of Back-flowproblem is Requires careful design to minimize IJ01, IJ03, IJ05, locatedbehind inlet back-flow by arranging the eliminated the negative pressurebehind the IJ06 the ink- ink-pushing surface of the paddle IJ07, IJ10,IJ11, pushing actuator between the inlet and the IJ14 surface nozzle.IJ16, IJ22, IJ23, IJ25 IJ28, IJ31, IJ32, IJ33 IJ34, IJ35, IJ36, IJ39IJ40, IJ41 Part of the The actuator and a wall of the ink Significantreductions in Small increase in fabrication IJ07, IJ20, IJ26, actuatorchamber are arranged so that the back-flow can be achieved complexityIJ38 moves to shut motion of the actuator closes off Compact designspossible off the inlet the inlet. Nozzle In some configurations of inkjet, Ink back-flow problem is None related to ink back-flow onSilverbrook, EP actuator does there is no expansion or eliminatedactuation 0771 658 A2 and not result in movement of an actuator whichrelated patent ink back-flow may cause ink back-flow throughapplications the inlet. Valve-jet Tone-jet IJ08, IJ13, IJ15, IJ17 IJ18,IJ19, IJ21

[0172] NOZZLE CLEARING METHOD Nozzle Clearing method DescriptionAdvantages Disadvantages Examples Normal nozzle All of the nozzles arefired No added complexity on May not be sufficient to displace Most inkjet systems firing periodically, before the ink has a the print headdried ink IJ01-IJ07, IJ09-IJ12 chance to dry. When not in use IJ14,IJ16, IJ20, the nozzles are sealed (capped) IJ22 against air. IJ23-IJ34,IJ36-IJ45 The nozzle firing is usually performed during a specialclearing cycle, after first moving the print head to a cleaning station.Extra power to In systems which heat the ink, but Can be highlyeffective if Requires higher drive voltage for Silverbrook, EP inkheater do not boil it under normal the heater is adjacent to theclearing 0771 658 A2 and situations, nozzle clearing can be nozzle Mayrequire larger drive transistors related patent achieved byover-powering the applications heater and boiling ink at the nozzle.Rapid The actuator is fired in rapid Does not require extraEffectiveness depends substantially May be used with: succession ofsuccession. In some drive circuits on the print upon the configurationof the inkjet IJ01-IJ07, IJ09-IJ11 actuator configurations, this maycause head nozzle IJ14, IJ16, IJ20, pulses heat build-up at the nozzlewhich Can be readily controlled IJ22 boils the ink, clearing the nozzle.and initiated by digital IJ23-IJ25, IJ27-IJ34 In other situations, itmay cause logic IJ36-IJ45 sufficient vibrations to dislodge cloggednozzles. Extra power to Where an actuator is not normally A simplesolution where Not suitable where there is a hard May be used with: inkpushing driven to the limit of its motion, applicable limit to actuatormovement IJ03, IJ09, IJ16, actuator nozzle clearing may be assisted byIJ20 providing an enhanced drive IJ23, IJ24, IJ25, signal to theactuator. IJ27 IJ29, IJ30, IJ31, IJ32 IJ39, IJ40, IJ41, IJ42 IJ43, IJ44,IJ45 Acoustic resonance An ultrasonic wave is applied to A high nozzleclearing High implementation cost if system IJ08, IJ13, IJ15, the inkchamber. This wave is of capability can be achieved does not alreadyinclude an acoustic IJ17 an appropriate amplitude and May be implementedat actuator IJ18, IJ19, IJ21 frequency to cause sufficient force verylow cost in systems at the nozzle to clear blockages. which alreadyinclude This is easiest to achieve if the acoustic actuators ultrasonicwave is at a resonant frequency of the ink cavity. Nozzle Amicrofabricated plate is pushed Can clear severely clogged Accuratemechanical alignment is Silverbrook, EP clearing plate against thenozzles. The plate has nozzles required 0771 658 A2 and a post for everynozzle. The array Moving parts are required related patent of postsThere is risk of damage to the nozzles applications Accurate fabricationis required Ink pressure The pressure of the ink is May be effectivewhere Requires pressure pump or other May be used with pulse temporarilyincreased so that ink other methods cannot be pressure actuator all IJseries ink jets streams from all of the nozzles. used Expensive This maybe used in conjunction Wasteful of ink with actuator energizing. Printhead A flexible ‘blade’ is wiped across Effective for planar printDifficult to use if print head surface is Many ink jet wiper the printhead surface. The blade head surfaces non-planar or very fragile systemsis usually fabricated from a Low cost Requires mechanical parts flexiblepolymer, e.g. rubber or Blade can wear out in high volume syntheticelastomer. print systems Separate ink A separate heater is provided atCan be effective where Fabrication complexity Can be used with boilingheater the nozzle although the normal other nozzle clearing many IJseries ink drop e-ection mechanism does methods cannot be used jets notrequire it. The heaters do not Can be implemented at no requireindividual drive circuits, additional cost in some as many nozzles canbe cleared inkjet configurations simultaneously, and no imaging isrequired.

[0173] NOZZLE PLATE CONSTRUCTION Nozzle plate construction DescriptionAdvantages Disadvantages Examples Electroformed A nozzle plate isseparately Fabrication simplicity High temperatures and pressures areHewlett Packard nickel fabricated from electroformed required to bondnozzle plate Thermal Inkjet nickel, and bonded to the print Minimumthickness constraints head chip. Differential thermal expansion Laserablated Individual nozzle holes are No masks required Each hole must beindividually Canon Bubblejet or drilled ablated by an intense UV laserin Can be quite fast formed 1988 Sercel et al., polymer a nozzle plate,which is typically a Some control over nozzle Special equipment requiredSPIE, Vol. 998 polymer such as polyimide or profile is possible Slowwhere there are many thousands Excimer Beam polysulphone Equipmentrequired is of nozzles per print head Applications, pp. relatively lowcost May produce thin burrs at exit holes 76-83 1993 Watanabe et al.,U.S. Pat. No. 5,208,604 Silicon A separate nozzle plate is High accuracyis attainable Two part construction K. Bean, IEEE micromachinedmicromachined from single High cost Transactions on crystal silicon, andbonded to the Requires precision alignment Electron Devices, print headwafer. Nozzles may be clogged by adhesive Vol. ED-25, No. 10, 1978, pp1185-1195 Xerox 1990 Hawkins et al., U.S. Pat. No. 4,899,181 Glass Fineglass capillaries are drawn No expensive equipment Very small nozzlesizes are difficult 1970 Zoltan U.S. Pat. No. capillaries from glasstubing. This method required to form 3,683,212 has been used for makingSimple to make single Not suited for mass production individual nozzles,but is difficult nozzles to use for bulk manufacturing of print headswith thousands of nozzles. Monolithic, The nozzle plate is deposited asa High accuracy (<1 μm) Requires sacrificial layer under theSilverbrook, EP surface layer using standard VLSI Monolithic nozzleplate to form the nozzle 0771 658 A2 and micromachined depositiontechniques. Nozzles Low cost chamber related patent using VLSI areetched in the nozzle plate Existing processes can be Surface may befragile to the touch applications lithographic using VLSI lithographyand used IJ01, IJ02, IJ04, processes etching. IJ11 IJ12, IJ17, IJ18,IJ20 IJ22, IJ24, IJ27, IJ28 IJ29, 1130, IJ31, IJ32 IJ33, IJ34, IJ36,IJ37 IJ38, IJ39, IJ40, IJ41 IJ42, IJ43, IJ44 Monolithic, The nozzleplate is a buried etch High accuracy (<1 μm) Requires long etch timesIJ03, IJ05, IJ06, etched stop in the wafer. Nozzle Monolithic Requires asupport wafer IJ07 through chambers are etched in the front Low costIJ08, IJ09, IJ10, substrate of the wafer, and the wafer is Nodifferential expansion IJ13 thinned from the back side. IJ14, IJ15,IJ16, Nozzles are then etched in the IJ19 etch stop layer. IJ21, IJ23,IJ25, IJ26 No nozzle Various methods have been tried No nozzles tobecome Difficult to control drop position Ricoh 1995 Sekiya plate toeliminate the nozzles entirely, clogged accurately et al U.S. Pat. No.5,412,413 to prevent nozzle clogging. These Crosstalk problems 1993Hadimioglu et al include thermal bubble EUP 550,192 mechanisms andacoustic lens 1993 Elrod et al mechanisms EUP 572,220 Trough Each dropejector has a trough Reduced manufacturing Drop firing direction issensitive to IJ35 through which a paddle moves. complexity wicking.There is no nozzle plate. Monolithic Nozzle slit The elimination ofnozzle holes No nozzles to become Difficult to control drop position1989 Saito et al U.S. Pat. No. instead of and replacement by a slitclogged accurately 4,799,068 individual encompassing many actuatorCrosstalk problems nozzles positions reduces nozzle clogging, butincreases crosstalk due to ink surface waves

[0174] DROP EJECTION DIRECTION Ejection direction Description AdvantagesDisadvantages Examples Edge Ink flow is along the surface of Simpleconstruction Nozzles limited to edge Canon (‘edge the chip, and inkdrops are ejected No silicon etching High resolution is difficultBubblejet 1979 shooter') from the chip edge. required Fast colorprinting requires one Endo et al GB Good heat sinking via print head percolor patent 2,007,162 substrate Xerox heater-in- Mechanically strongpit 1990 Ease of chip handing Hawkins et al U.S. Pat. No. 4,899,181Tone-jet Surface Ink flow is along the surface of No bulk siliconMaximum ink flow is severely Hewlett- (‘roof shooter’) the chip, and inkdrops are ejected etching required restricted Packard TIJ from the chipsurface, normal to Silicon can make an 1982 Vaught et the plane of thechip. effective heat sink al U.S. Pat. No. Mechanical strength 4,490,728IJ02, IJ11, IJ12, IJ20 IJ22 Through chip, Ink flow is through the chip,and High ink flow Requires bulk silicon etching Silverbrook, EP forwardink drops are ejected from the Suitable for pagewidth 0771 658 A2 (‘upshooter’) front surface of the chip. print and related High nozzlepacking patent density therefore low applications manufacturing costIJ04, IJ17, IJ18, IJ24 IJ27-IJ45 Through chip, Ink flow is through thechip, and High ink flow Requires wafer thinning IJ01, IJ03, IJ05,reverse ink drops are ejected from the rear Suitable for pagewidthRequires special handling during IJ06 (‘down surface of the chip. printmanufacture IJ07, IJ08, IJ09, shooter’) High nozzle packing IJ10 densitytherefore low IJ13, IJ14, IJ15, manufacturing cost IJ16 IJ19, IJ21,IJ23, IJ25 IJ26 Through Ink flow is through the actuator, Suitable forPagewidth print heads require Epson Stylus actuator which is notfabricated as part of piezoelectric print several thousand connectionsto Tektronix hot the same substrate as the drive heads drive circuitsmelt transistors. Cannot be manufactured in piezoelectric ink standardCMOS fabs jets Complex assembly required

[0175] INK TYPE Ink type Description Advantages Disadvantages ExamplesAqueous, dye Water based ink which typically Environmentally friendlySlow drying Most existing contains: water, dye, surfactant, No odorCorrosive inkjets humectant, and biocide. Bleeds on paper All IJ seriesink jets Modem ink dyes have high water- May strikethrough Silverbrook,EP fastness, light fastness Cockles paper 0771 658 A2 and related patentapplications Aqueous, Water based ink which typically Environmentallyfriendly Slow drying IJ02, IJ04, IJ21, pigment contains: water, pigment,No odor Corrosive IJ26 surfactant, humectant, and Reduced bleed Pigmentmay clog nozzles IJ27, IJ30 biocide. Reduced wicking Pigment may clogactuator Silverbrook, EP Pigments have an advantage in Reducedstrikethrough mechanisms 0771 658 A2 and reduced bleed, wicking andCockles paper related patent strikethrough. applications Piezoelectricink-jets Thermal ink jets (with significant restrictions) Methyl EthylMEK is a highly volatile solvent Very fast drying Odorous All IJ seriesink jets Ketone (MEK) used for industrial printing on Prints on variousFlammable difficult surfaces such as substrates such as metals aluminumcans. and plastics Alcohol Alcohol based inks can be used Fast dryingSlight odor All IJ series ink jets (ethanol, 2- where the printer mustoperate at Operates at sub-freezing Flammable butanol, and temperaturesbelow the freezing temperatures others) point of water. An example ofthis Reduced paper cockle is in-camera consumer Low cost photographicprinting. Phase change The ink is solid at room No drying time-ink Highviscosity Tektronix hot melt (hot melt) temperature, and is melted inthe instantly freezes on the Printed ink typically has a ‘waxy’ feelpiezoelectric ink jets print head before jetting. Hot melt print mediumPrinted pages may ‘block’ 1989 Nowak U.S. Pat. No. inks are usually waxbased, with a Almost any print medium Ink temperature may be above the4,820,346 melting point around 80° C. After can be used curie point ofpermanent magnets All IJ series ink jets jetting the ink freezes almostNo paper cockle occurs Ink heaters consume power instantly uponcontacting the print No wicking occurs Long warm-up time medium or atransfer roller. No bleed occurs No strikethrough occurs Oil Oil basedinks are extensively High solubility medium High viscosity: this is asignificant All IJ series ink jets used in offset printing. They havefor some dyes limitation for use in inkjets, which advantages inimproved Does not cockle paper usually require a low viscosity. Somecharacteristics on paper Does not wick through short chain andmulti-branched oils (especially no wicking or cockle). paper have asufficiently low viscosity. Oil soluble dies and pigments are Slowdrying required. Microemulsion A microemulsion is a stable, self Stopsink bleed Viscosity higher than water All IJ series ink jets formingemulsion of oil, water, High dye solubility Cost is slightly higher thanwater and surfactant. The characteristic Water, oil, and based ink dropsize is less than 100 nm, and amphiphilic soluble dies High surfactantconcentration is determined by the preferred can be used required(around 5%) curvature of the surfactant. Can stabilize pigmentsuspensions

[0176] Ink Jet Printing

[0177] A large number of new forms of ink jet printers have beendeveloped to facilitate alternative ink jet technologies for the imageprocessing and data distribution system. Various combinations of ink jetdevices can be included in printer devices incorporated as part of thepresent invention. Australian Provisional Applications relating to theseink jets which are specifically incorporated by cross reference include:Australian Provisional Number Filing Date Title PO8066 15-Jul-97 ImageCreation Method and Apparatus (IJ01) PO8072 15-Jul-97 Image CreationMethod and Apparatus (IJ02) PO8040 15-Jul-97 Image Creation Method andApparatus (IJ03) PO8071 15-Jul-97 Image Creation Method and Apparatus(IJ04) PO8047 15-Jul-97 Image Creation Method and Apparatus (IJ05)PO8035 15-Jul-97 Image Creation Method and Apparatus (IJ06) PO804415-Jul-97 Image Creation Method and Apparatus (IJ07) PO8063 15-Jul-97Image Creation Method and Apparatus (IJ08) PO8057 15-Jul-97 ImageCreation Method and Apparatus (IJ09) PO8056 15-Jul-97 Image CreationMethod and Apparatus (IJ10) PO8069 15-Jul-97 Image Creation Method andApparatus (IJ11) PO8049 15-Jul-97 Image Creation Method and Apparatus(IJ12) PO8036 15-Jul-97 Image Creation Method and Apparatus (IJ13)PO8048 15-Jul-97 Image Creation Method and Apparatus (IJ14) PO807015-Jul-97 Image Creation Method and Apparatus (IJ15) PO8067 15-Jul-97Image Creation Method and Apparatus (IJ16) PO8001 15-Jul-97 ImageCreation Method and Apparatus (IJ17) PO8038 15-Jul-97 Image CreationMethod and Apparatus (IJ18) PO8033 15-Jul-97 Image Creation Method andApparatus (IJ19) PO8002 15-Jul-97 Image Creation Method and Apparatus(IJ20) PO8068 15-Jul-97 Image Creation Method and Apparatus (IJ21)PO8062 15-Jul-97 Image Creation Method and Apparatus (IJ22) PO803415-Jul-97 Image Creation Method and Apparatus (IJ23) PO8039 15-Jul-97Image Creation Method and Apparatus (IJ24) PO8041 15-Jul-97 ImageCreation Method and Apparatus (IJ25) PO8004 15-Jul-97 Image CreationMethod and Apparatus (IJ26) PO8037 15-Jul-97 Image Creation Method andApparatus (IJ27) PO8043 15-Jul-97 Image Creation Method and Apparatus(IJ28) PO8042 15-Jul-97 Image Creation Method and Apparatus (IJ29)PO8064 15-Jul-97 Image Creation Method and Apparatus (IJ30) PO938923-Sep-97 Image Creation Method and Apparatus (IJ31) PO9391 23-Sep-97Image Creation Method and Apparatus (IJ32) PP0888 12-Dec-97 ImageCreation Method and Apparatus (IJ33) PP0891 12-Dec-97 Image CreationMethod and Apparatus (IJ34) PP0890 12-Dec-97 Image Creation Method andApparatus (IJ35) PP0873 12-Dec-97 Image Creation Method and Apparatus(IJ36) PP0993 12-Dec-97 Image Creation Method and Apparatus (IJ37)PP0890 12-Dec-97 Image Creation Method and Apparatus (IJ38) PP139819-Jan-98 An Image Creation Method and Apparatus (IJ39) PP2592 25-Mar-98An Image Creation Method and Apparatus (IJ40) PP2593 25-Mar-98 ImageCreation Method and Apparatus (IJ41) PP3991 9-Jun-98 Image CreationMethod and Apparatus (IJ42) PP3987 9-Jun-98 Image Creation Method andApparatus (IJ43) PP3985 9-Jun-98 Image Creation Method and Apparatus(IJ44) PP3983 9-Jun-98 Image Creation Method and Apparatus (IJ45)

[0178] Ink Jet Manufacturing

[0179] Further, the present application may utilize advancedsemiconductor fabrication techniques in the construction of large arraysof ink jet printers. Suitable manufacturing techniques are described inthe following Australian provisional patent specifications incorporatedhere by cross-reference: Australian Provisional Number Filing Date TitlePO7935 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus(IJM01) PO7936 15-Jul-97 A Method of Manufacture of an Image CreationApparatus (IJM02) PO7937 15-Jul-97 A Method of Manufacture of an ImageCreation Apparatus (IJM03) PO8061 15-Jul-97 A Method of Manufacture ofan Image Creation Apparatus (IJM04) PO8054 15-Jul-97 A Method ofManufacture of an Image Creation Apparatus (IJM05) PO8065 15-Jul-97 AMethod of Manufacture of an Image Creation Apparatus (IJM06) PO805515-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM07)PO8053 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus(IJM08) PO8078 15-Jul-97 A Method of Manufacture of an Image CreationApparatus (IJM09) PO7933 15-Jul-97 A Method of Manufacture of an ImageCreation Apparatus (IJM10) PO7950 15-Jul-97 A Method of Manufacture ofan Image Creation Apparatus (IJM11) PO7949 15-Jul-97 A Method ofManufacture of an Image Creation Apparatus (IJM12) PO8060 15-Jul-97 AMethod of Manufacture of an Image Creation Apparatus (IJM13) PO805915-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM14)PO8073 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus(IJM15) PO8076 15-Jul-97 A Method of Manufacture of an Image CreationApparatus (IJM16) PO8075 15-Jul-97 A Method of Manufacture of an ImageCreation Apparatus (IJM17) PO8079 15-Jul-97 A Method of Manufacture ofan Image Creation Apparatus (IJM18) PO8050 15-Jul-97 A Method ofManufacture of an Image Creation Apparatus (IJM19) PO8052 15-Jul-97 AMethod of Manufacture of an Image Creation Apparatus (IJM20) PO794815-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM21)PO7951 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus(IJM22) PO8074 15-Jul-97 A Method of Manufacture of an Image CreationApparatus (IJM23) PO7941 15-Jul-97 A Method of Manufacture of an ImageCreation Apparatus (IJM24) PO8077 15-Jul-97 A Method of Manufacture ofan Image Creation Apparatus (IJM25) PO8058 15-Jul-97 A Method ofManufacture of an Image Creation Apparatus (IJM26) PO8051 15-Jul-97 AMethod of Manufacture of an Image Creation Apparatus (IJM27) PO804515-Jul-97 A Method of Manufacture of an Image Creation Apparatus (IJM28)PO7952 15-Jul-97 A Method of Manufacture of an Image Creation Apparatus(IJM29) PO8046 15-Jul-97 A Method of Manufacture of an Image CreationApparatus (IJM30) PO8503 11-Aug-97 A Method of Manufacture of an ImageCreation Apparatus (IJM30a) PO9390 23-Sep-97 A Method of Manufacture ofan Image Creation Apparatus (IJM31) PO9392 23-Sep-97 A Method ofManufacture of an Image Creation Apparatus (IJM32) PP0889 12-Dec-97 AMethod of Manufacture of an Image Creation Apparatus (IJM35) PP088712-Dec-97 A Method of Manufacture of an Image Creation Apparatus (IJM36)PP0882 12-Dec-97 A Method of Manufacture of an Image Creation Apparatus(IJM37) PP0874 12-Dec-97 A Method of Manufacture of an Image CreationApparatus (IJM38) PP1396 19-Jan-98 A Method of Manufacture of an ImageCreation Apparatus (IJM39) PP2591 25-Mar-98 A Method of Manufacture ofan Image Creation Apparatus (IJM41) PP3989 9-Jun-98 A Method ofManufacture of an Image Creation Apparatus (IJM40) PP3990 9-Jun-98 AMethod of Manufacture of an Image Creation Apparatus (IJM42) PP39869-Jun-98 A Method of Manufacture of an Image Creation Apparatus (IJM43)PP3984 9-Jun-98 A Method of Manufacture of an Image Creation Apparatus(IJM44) PP3982 9-Jun-98 A Method of Manufacture of an Image CreationApparatus (IJM45)

[0180] Fluid Supply

[0181] Further, the present application may utilize an ink deliverysystem to the ink jet head. Delivery systems relating to the supply ofink to a series of ink jet nozzles are described in the followingAustralian provisional patent specifications, the disclosure of whichare hereby incorporated by cross-reference: Australian ProvisionalFiling Number Date Title PO8003 15-Jul-97 Supply Method and Apparatus(F1) PO8005 15-Jul-97 Supply Method and Apparatus (F2) PO9404 23-Sep-97A Device and Method (F3)

[0182] MEMS Technology

[0183] Further, the present application may utilize advancedsemiconductor microelectromechanical techniques in the construction oflarge arrays of ink jet printers. Suitable microelectromechanicaltechniques are described in the following Australian provisional patentpatent specifications incorporated here by cross-reference: AustralianProvisional Filing Number Date Title PO7943 15-Jul-97 A device (MEMS01)PO8006 15-Jul-97 A device (MEMS02) PO8007 15-Jul-97 A device (MEMS03)PO8008 15-Jul-97 A device (MEMS04) PO8010 15-Jul-97 A device (MEMS05)PO8011 15-Jul-97 A device (MEMS06) PO7947 15-Jul-97 A device (MEMS07)PO7945 15-Jul-97 A device (MEMS08) PO7944 15-Jul-97 A device (MEMS09)PO7946 15-Jul-97 A device (MEMS10) PO9393 23-Sep-97 A Device and Method(MEMS11) PP0875 12-Dec-97 A Device (MEMS12) PP0894 12-Dec-97 A Deviceand Method (MEMS13)

[0184] IR Technologies

[0185] Further, the present application may include the utilization of adisposable camera system such as those described in the followingAustralian provisional patent specifications incorporated here bycross-reference: Australian Provisional Filing Number Date Title PP089512-Dec-97 An Image Creation Method and Apparatus (IR01) PP0870 12-Dec-97A Device and Method (IR02) PP0869 12-Dec-97 A Device and Method (IR04)PP0887 12-Dec-97 Image Creation Method and Apparatus (IR05) PP088512-Dec-97 An Image Production System (IR06) PP0884 12-Dec-97 ImageCreation Method and Apparatus (IR10) PP0886 12-Dec-97 Image CreationMethod and Apparatus (IR12) PP0871 12-Dec-97 A Device and Method (IR13)PP0876 12-Dec-97 An Image Processing Method and Apparatus (IR14) PP087712-Dec-97 A Device and Method (IR16) PP0878 12-Dec-97 A Device andMethod (IR17) PP0879 12-Dec-97 A Device and Method (IR18) PP088312-Dec-97 A Device and Method (IR19) PP0880 12-Dec-97 A Device andMethod (IR20) PP0881 12-Dec-97 A Device and Method (IR21)

[0186] DotCard Technologies

[0187] Further, the present application may include the utilization of adata distribution system such as that described in the followingAustralian provisional patent specifications incorporated here bycross-reference: Australian Provisional Number Filing Date Title PP237016-Mar-98 Data Processing Method and Apparatus (Dot01) PP2371 16-Mar-98Data Processing Method and Apparatus (Dot02)

[0188] Artcam Technologies

[0189] Further, the present application may include the utilization ofcamera and data processing techniques such as an Artcam type device asdescribed in the following Australian provisional patent specificationsincorporated here by cross-reference: Australian Provisional NumberFiling Date Title PO7991 15-Jul-97 Image Processing Method and Apparatus(ART01) PO8505 11-Aug-97 Image Processing Method and Apparatus (ART01a)PO7988 15-Jul-97 Image Processing Method and Apparatus (ART02) PO799315-Jul-97 Image Processing Method and Apparatus (ART03) PO8012 15-Jul-97Image Processing Method and Apparatus (ART05) PO8017 15-Jul-97 ImageProcessing Method and Apparatus (ART06) PO8014 15-Jul-97 Media Device(ART07) PO8025 15-Jul-97 Image Processing Method and Apparatus (ART08)PO8032 15-Jul-97 Image Processing Method and Apparatus (ART09) PO799915-Jul-97 Image Processing Method and Apparatus (ART10) PO7998 15-Jul-97Image Processing Method and Apparatus (ART11) PO8031 15-Jul-97 ImageProcessing Method and Apparatus (ART12) PO8030 15-Jul-97 Media Device(ART13) PO8498 11-Aug-97 Image Processing Method and Apparatus (ART14)PO7997 15-Jul-97 Media Device (ART15) PO7979 15-Jul-97 Media Device(ART16) PO8015 15-Jul-97 Media Device (ART17) PO7978 15-Jul-97 MediaDevice (ART18) PO7982 15-Jul-97 Data Processing Method and Apparatus(ART19) PO7989 15-Jul-97 Data Processing Method and Apparatus (ART20)PO8019 15-Jul-97 Media Processing Method and Apparatus (ART21) PO798015-Jul-97 Image Processing Method and Apparatus (ART22) PO7942 15-Jul-97Image Processing Method and Apparatus (ART23) PO8018 15-Jul-97 ImageProcessing Method and Apparatus (ART24) PO7938 15-Jul-97 ImageProcessing Method and Apparatus (ART25) PO8016 15-Jul-97 ImageProcessing Method and Apparatus (ART26) PO8024 15-Jul-97 ImageProcessing Method and Apparatus (ART27) PO7940 15-Jul-97 Data ProcessingMethod and Apparatus (ART28) PO7939 15-Jul-97 Data Processing Method andApparatus (ART29) PO8501 11-Aug-97 Image Processing Method and Apparatus(ART30) PO8500 11-Aug-97 Image Processing Method and Apparatus (ART31)PO7987 15-Jul-97 Data Processing Method and Apparatus (ART32) PO802215-Jul-97 Image Processing Method and Apparatus (ART33) PO8497 11-Aug-97Image Processing Method and Apparatus (ART30) PO8029 15-Jul-97 SensorCreation Method and Apparatus (ART36) PO7985 15-Jul-97 Data ProcessingMethod and Apparatus (ART37) PO8020 15-Jul-97 Data Processing Method andApparatus (ART38) PO8023 15-Jul-97 Data Processing Method and Apparatus(ART39) PO9395 23-Sep-97 Data Processing Method and Apparatus (ART4)PO8021 15-Jul-97 Data Processing Method and Apparatus (ART40) PO850411-Aug-97 Image Processing Method and Apparatus (ART42) PO8000 15-Jul-97Data Processing Method and Apparatus (ART43) PO7977 15-Jul-97 DataProcessing Method and Apparatus (ART44) PO7934 15-Jul-97 Data ProcessingMethod and Apparatus (ART45) PO7990 15-Jul-97 Data Processing Method andApparatus (ART46) PO8499 11-Aug-97 Image Processing Method and Apparatus(ART47) PO8502 11-Aug-97 Image Processing Method and Apparatus (ART48)PO7981 15-Jul-97 Data Processing Method and Apparatus (ART50) PO798615-Jul-97 Data Processing Method and Apparatus (ART51) PO7983 15-Jul-97Data Processing Method and Apparatus (ART52) PO8026 15-Jul-97 ImageProcessing Method and Apparatus (ART53) PO8027 15-Jul-97 ImageProcessing Method and Apparatus (ART54) PO8028 15-Jul-97 ImageProcessing Method and Apparatus (ART56) PO9394 23-Sep-97 ImageProcessing Method and Apparatus (ART57) PO9396 23-Sep-97 Data ProcessingMethod and Apparatus (ART58) PO9397 23-Sep-97 Data Processing Method andApparatus (ART59) PO9398 23-Sep-97 Data Processing Method and Apparatus(ART60) PO9399 23-Sep-97 Data Processing Method and Apparatus (ART61)PO9400 23-Sep-97 Data Processing Method and Apparatus (ART62) PO940123-Sep-97 Data Processing Method and Apparatus (ART63) PO9402 23-Sep-97Data Processing Method and Apparatus (ART64) PO9403 23-Sep-97 DataProcessing Method and Apparatus (ART65) PO9405 23-Sep-97 Data ProcessingMethod and Apparatus (ART66) PP0959 16-Dec-97 A Data Processing Methodand Apparatus (ART68) PP1397 19-Jan-98 A Media Device (ART69)

We claim:
 1. A supply of print media for use in a digital camera havinga printer for printing an image captured by the camera onto the printmedia, the print media being pre-marked with tokens designating thatpostage has been paid so that each image printed out on the print mediahas one such token associated with it.
 2. The supply of print mediaaccording to claim 1 wherein the print media is in the form of a roll,the tokens being pre-printed at regularly spaced intervals on onesurface of the print media.
 3. The print media of claim 2 in which eachtoken has an address zone and a blank zone for writing associated withit on said one surface to provide a postcard effect.
 4. The print mediaof claim 1 in which the token is in a currency of a country in which thecamera is bought, with a notice to that effect being carried on anexterior of the camera.